BBC's new Weather website - where have the isobars gone?

[Ian Jackson]

The BBC have introduced a new, improved style of presenting the weather.

On their website, there no longer appears to be a proper 'Jack Scott'
weather map (Surface Pressure Chart), as per
<https://www.metoffice.gov.uk/public/weather/surface-pressure/#?tab=surfa
cePressureColour&fcTime=1517918400>

Is it there somewhere, and I can't find it - or do the BBC feel that
nobody was interested?
--
Ian

[Robin]

like this?

https://www.metoffice.gov.uk/public/weather/forecast/map#?map=Pressure&fcTime=1517968800&zoom=5&lon=-4.00&lat=55.01



--
Robin
reply-to address is (intended to be) valid

[Andy Burns]

Can't see one, they show Eire as "dimmed" out, but instead of dimming
continental europe, they've removed it completely and replaced it with
clouds.

Also why have they've revamped the weather section, but still not
brought html5 video for the forecasts, it still whines about needing flash.

[Robin]

ooops, wrong tab in Firefox. Try

http://www.bbc.co.uk/weather/2635167

and then the "Pressure " tab there

[Andrew]

On 07/02/2018 10:32, Ian Jackson wrote:

I just use this site :-

http://www.anotherharddayattheoffice.co.uk/charts.html#charts

[Java Jive]

On 07/02/2018 10:32, Ian Jackson wrote:

I use the Met Office mobile one, mobile because the desktop version
inserts ads.

https://www.metoffice.gov.uk/mobile/surface-pressure/

[John Hall]

In message <yN688cEs...@brattleho.plus.com>, Ian Jackson
<ianREMOVET...@g3ohx.co.uk> writes

I suspect that MeteoGroup, who have now taken over from the Met Office,
should take much of the credit, though presumably the BBC would have had
an input.
--
John Hall
"Hegel was right when he said that we learn from history
that man can never learn anything from history."
George Bernard Shaw (1856-1950)

[AnthonyL]

There was something on the radio yesterday with the presenter being
excited about the changes to the BBC weather presentation and no
longer using brown or something.

I like playing with

https://earth.nullschool.net/


--
AnthonyL

[Peter Duncanson]

On Wed, 7 Feb 2018 10:32:12 +0000, Ian Jackson
<ianREMOVET...@g3ohx.co.uk> wrote:

I suspect they consider that very few viewers can understand surface
pressure charts.

There is information about the recent changes here:
http://www.bbc.co.uk/weather/about/42822208

Pressure - where are the pressure maps?

You can find pressure charts on forecast location pages. Go to a
location, such as Cardiff, scroll down the page to the map.

Then just select the 'Full screen' option' to open the map and
select the 'pressure' key on the left. Toggle on the pressure data
layer to see pressure for your region, country or even globe.

I.e. go to this page:
https://www.bbc.co.uk/weather/0

Click on one of the locations named on the map.
A page will be shown for that location.
For instance Manchester:
https://www.bbc.co.uk/weather/0/2643123

Scroll down the page to the map and click on "Full Screen" at the bottom
right of the map.
Then click on "Key and options" at the top left and select "Pressure"
(You may need to scroll down through the options.)
It is possible to zoom out to see a larger area including the whole of
the World.

Those surface pressure charts are "simpler" than the useful ones on the
Met Office site.

--
Peter Duncanson
(in uk.tech.digital-tv)

[Peter Duncanson]

On Wed, 7 Feb 2018 13:00:06 +0000, Java Jive <ja...@evij.com.invalid>
wrote:

I use the Metcheck website. There are apps available:
https://www.metcheck.com/

[Mark]

Still, it's vastly inferior IMHO.

--
<insert witty sig here>

[Ian Jackson]

In message <la1m7dp29sddf3l9l...@4ax.com>, Peter Duncanson
<ma...@peterduncanson.net> writes

I eventually found it - but it's not the traditional meteorological map
(no fronts with arrow heads and bowler hats). But thanks for the
guidance!

>
>Those surface pressure charts are "simpler" than the useful ones on the
>Met Office site.

Indeed. However, you could hardly call the traditional type of chart
'complicated'.
>

--
Ian

[MR]

Try this one:

https://www.ventusky.com/

MartinR

> --
> AnthonyL

[Brian Gaff]

Hang on what is difficult about pressure. it is after all what drives the
weather.
Now I cannot see the maps any more but given a list of pressures and their
trending, one can construct the areas in ones mind.
Brian

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"Ian Jackson" <ianREMOVET...@g3ohx.co.uk> wrote in message
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[Adrian Caspersz]

On 08/02/18 10:25, Martin wrote:

> On Wed, 7 Feb 2018 09:21:32 -0800 (PST), MR <martin...@googlemail.com>
> wrote:

>>> I like playing with
>>>
>>> https://earth.nullschool.net/
>>>
>>>
>> Try this one:
>>
>> https://www.ventusky.com/
>

> I recommended that here earlier :-)
>

I can hear the wind howling outside, and now looking at that I'm now
feeling colder.

Thanks! :(

--
Adrian C

[Mike Cooper]

This is good

https://www.met.ie/forecasts/atlantic-charts/precipitation-pressure

[Woody]

Probably because the average <50 (or maybe less!) viewer of today hasn't
got a clue what its about.

Has anyone else noticed that organisations such as XCWeather,
Weatherwatch, and the Irish Weather Service (link above) are quite happy
to forecast 7 days ahead but the good old BBC (and for TV purposes the
Met Office) only ever do three?

[MB]

On 21/02/2022 09:59, Woody wrote:
> Probably because the average <50 (or maybe less!) viewer of today hasn't
> got a clue what its about.
>
> Has anyone else noticed that organisations such as XCWeather,
> Weatherwatch, and the Irish Weather Service (link above) are quite happy
> to forecast 7 days ahead but the good old BBC (and for TV purposes the
> Met Office) only ever do three?

I presume they can tell what pages people are looking at and decided
that the average viewer does not want the synoptic chart and might be
confused by it.

They can easily be viewed on the Met Office site.

https://www.metoffice.gov.uk/weather/maps-and-charts/surface-pressure

I am sure you can download the raw data if you wish to do your own
forecasting. :-)

[Andy Burns]

Woody wrote:

> Has anyone else noticed that organisations such as XCWeather, Weatherwatch, and
> the Irish Weather Service (link above) are quite happy to forecast 7 days ahead
> but the good old BBC (and for TV purposes the Met Office) only ever do three?

On the contrary, the BBC weather app forecasts in 1 hour slots for 14 days
ahead, which strikes me as an utterly pointless level of detail.

[John Hall]

>On Wednesday, 7 February 2018 at 10:32:21 UTC, Ian Jackson wrote:
>> The BBC have introduced a new, improved style of presenting the weather.
>>
>> On their website, there no longer appears to be a proper 'Jack Scott'
>> weather map (Surface Pressure Chart), as per
>> <https://www.metoffice.gov.uk/public/weather/surface-pressure/#?tab=surfa
>> cePressureColour&fcTime=1517918400>
>>
>> Is it there somewhere, and I can't find it - or do the BBC feel that
>> nobody was interested?

I've only just spotted this. The obvious comment is that that's the Met
Office's website, and nothing to do with the BBC (who don't even use the
Met Office's forecasts any more, but get them from an outfit called
Meteogroup). (Dis)credit where it's due.
--
John Hall
"Home is heaven and orgies are vile,
But you *need* an orgy, once in a while."
Ogden Nash (1902-1971)

[MB]

On 21/02/2022 10:17, Andy Burns wrote:
> On the contrary, the BBC weather app forecasts in 1 hour slots for 14 days
> ahead, which strikes me as an utterly pointless level of detail.

The BBC do a "monthly outlook" but they learnt long ago that long
distance forecasts are not accurate and always have warnings with them
but they still get complaints if not absolutely accurate.

The Today programme earlier was talking to someone whose electricity
supply with be off until Wednesday at least, being a country person he
was quite understanding and not moaning as so often happens. I think he
was the same person who was saying how accurate the forecasts of the
storms had been.

Usually the moaners have listened to a two minute summary forecast for
the whole UK then wondered why it was not right for their home!

[Jeff Layman]

On 21/02/2022 08:57, Mike Cooper wrote:

If you're interested in just about every aspect of what the weather is
doing anywhere in the world, then the best website I've found is
https://earth.nullschool.net/. This url centres on the UK:
<https://earth.nullschool.net/#2022/02/21/2000Z/wind/isobaric/1000hPa/orthographic=-6.04,53.98,3226>

If you click on "earth" at bottom left, you can change the parameters of
what you're looking at. It's worth a play, but you may find yourself
spending rather a lot of time on the site!

--

Jeff

[Andy Burns]

MB wrote:

> The BBC do a "monthly outlook"

And I'm sure that sometimes the weather patterns are more locked-in than at
other times, and they can be a bit more hand-wavy if it's uncler which way it's
going to go.

> but they learnt long ago that long distance
> forecasts are not accurate and always have warnings with them

I think before they switched from met office to meteo's WaaS, the app used to
give 1 hour slots for e.g. the next 3 days, then half day slots for about 4-5
days and finally one slot per day for another 2-3 days.

[Roderick Stewart]

On Mon, 21 Feb 2022 10:12:18 +0000, John Hall
<john_...@jhall.co.uk> wrote:

>>On Wednesday, 7 February 2018 at 10:32:21 UTC, Ian Jackson wrote:
>>> The BBC have introduced a new, improved style of presenting the weather.
>>>
>>> On their website, there no longer appears to be a proper 'Jack Scott'
>>> weather map (Surface Pressure Chart), as per
>>> <https://www.metoffice.gov.uk/public/weather/surface-pressure/#?tab=surfa
>>> cePressureColour&fcTime=1517918400>
>>>
>>> Is it there somewhere, and I can't find it - or do the BBC feel that
>>> nobody was interested?
>
>I've only just spotted this. The obvious comment is that that's the Met
>Office's website, and nothing to do with the BBC (who don't even use the
>Met Office's forecasts any more, but get them from an outfit called
>Meteogroup). (Dis)credit where it's due.

I like the visual presentation of the weather forecasts on the BBC
website, but last night's predicted wind speeds for my area were about
10mph less scary on the Met Office site. That's quite a discrepancy.

Rod.

[Brian Gaff (Sofa)]

Maybe renaming them to isohectopascals was too far for them to go?
Brian

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[Brian Gaff (Sofa)]

Apparently you can get three for nothing but the further you go the more it
will cost you if you need it in detail.

Brian

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"Woody" <harro...@ntlworld.com> wrote in message
news:suvnps$b3m$1...@dont-email.me...

[Brian Gaff (Sofa)]

I wonder if the change in pressures being signified by how close together
the lines run is actually explained any more? Surely its the simplest of
concepts to grasp that the closer together the more the wind blows as high
pressure is always trying to fill low.

Brian

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"MB" <M...@nospam.net> wrote in message news:suvob9$eu5$1...@dont-email.me...

[Brian Gaff (Sofa)]

Is it also so complicated to realise that warm air contains more water
vapour if it is in the area, but cold air lets it rain out?
Is it also hard to see that this interface is called the dew point and
gthus ion the ground, if both are exactly the same, ie temperature and the
dew point then its foggy damp ad wet as clouds form at ground level but the
higher pressure stops all of that occurring.


I also wonder how much the public know about why weather systems spin
around? It is because the bits nearer the equator are moving faster and the
drag forces a rotation. Cyclones one way anticyclones the other and each is
reversed in the different hemispheres. Chaos reigns at the equator.

Weather even on these basic levels is interesting even before you invoke
the sun angle and the tilt of the earth, reflectivity of te ground and
gasses that hold onto radiation.

Brian

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"Jeff Layman" <jmla...@invalid.invalid> wrote in message
news:suvq20$po0$1...@dont-email.me...

[David Woolley]

On 21/02/2022 12:06, Brian Gaff (Sofa) wrote:
> I wonder if the change in pressures being signified by how close together
> the lines run is actually explained any more? Surely its the simplest of
> concepts to grasp that the closer together the more the wind blows as high
> pressure is always trying to fill low.

Except that Coriolis forces mean the wind doesn't actually flow in the
right direction to fill the low pressure!

[Java Jive]

<pedant>I'm not sure 'force' is the right word there!</pedant>

--

Fake news kills!

I may be contacted via the contact address given on my website:
www.macfh.co.uk

[NY]

"Brian Gaff (Sofa)" <bri...@blueyonder.co.uk> wrote in message
news:suvv85$g2$1...@dont-email.me...

> I wonder if the change in pressures being signified by how close together
> the lines run is actually explained any more? Surely its the simplest of
> concepts to grasp that the closer together the more the wind blows as high
> pressure is always trying to fill low.

It's not entirely intuitive, the same as for contour lines on a map, but I'd
expect any children to be taught about contour lines (and probably isobar
lines) at school by the age of about 10.

But I wonder how many children of today have actually looked at an OS map,
as opposed to Google Map or Open Street Map) and have seen (and had
explained to them) contour lines.

Maps such as https://www.windy.com/?52.503,-2.648,6 take a different
approach and show the flow of wind (so their lines are roughly at 90 degrees
to isobar lines) which is easier to interpret in terms of speed and
direction.

[jon]

On Mon, 21 Feb 2022 14:18:54 +0000, Java Jive wrote:

> On 21/02/2022 14:01, David Woolley wrote:
>> On 21/02/2022 12:06, Brian Gaff (Sofa) wrote:
>>> I wonder if the  change in pressures being signified by how close
>>> together the lines run is actually explained any more? Surely its the
>>> simplest of concepts to grasp that the closer together the more the
>>> wind blows as high pressure is always trying to fill low.
>>
>> Except that Coriolis forces  mean the wind doesn't actually flow in the
>> right direction to fill the low pressure!
>
> <pedant>I'm not sure 'force' is the right word there!</pedant>

Enough force to blow off unattached items.

[noth...@aolbin.com]

On 21/02/2022 12:14, Brian Gaff (Sofa) wrote:
> Is it also so complicated to realise that warm air contains more water
> vapour if it is in the area, but cold air lets it rain out?
> Is it also hard to see that this interface is called the dew point and
> gthus ion the ground, if both are exactly the same, ie temperature and the
> dew point then its foggy damp ad wet as clouds form at ground level but the
> higher pressure stops all of that occurring.
>
>
> I also wonder how much the public know about why weather systems spin
> around? It is because the bits nearer the equator are moving faster and the
> drag forces a rotation. Cyclones one way anticyclones the other and each is
> reversed in the different hemispheres. Chaos reigns at the equator.
>
> Weather even on these basic levels is interesting even before you invoke
> the sun angle and the tilt of the earth, reflectivity of te ground and
> gasses that hold onto radiation.
> Brian
>

Mr Coriolis has a lot to answer for

[Pamela]

Lovely graphics. No forecast?

[Robin]

On 21/02/2022 14:18, Java Jive wrote:
> On 21/02/2022 14:01, David Woolley wrote:
>> On 21/02/2022 12:06, Brian Gaff (Sofa) wrote:
>>> I wonder if the  change in pressures being signified by how close
>>> together
>>> the lines run is actually explained any more? Surely its the simplest of
>>> concepts to grasp that the closer together the more the wind blows as
>>> high
>>> pressure is always trying to fill low.
>>
>> Except that Coriolis forces  mean the wind doesn't actually flow in
>> the right direction to fill the low pressure!
>
> <pedant>I'm not sure 'force' is the right word there!</pedant>
>

When I dabbled in physics many years ago "Coriolis force" was by
definition a fictional force so - unless the meaning has changed - it
seems an acceptable term in that context.

--
Robin
reply-to address is (intended to be) valid

[Java Jive]

Yeah, sure, :-), but, still being pedantic, that's not why storms spin,
which Brian has had a go at explaining elsewhere. AIUI, it should be
called 'the Coriolis effect', because AFAIAA there are no actual forces
involved, just differences in linear velocity at different latitudes on
a rotating object such as the earth. The rotational velocity is the
same everywhere on earth, 1 rpd, but linear velocity near the pole is
almost stationary, while linear velocity near the equator is almost
1,670 km/hr, thus air moving from the poles into an area of low pressure
at mid-latitudes tends to fall behind it, while air from the equator
tends to overtake it. The opposite is true of areas of high pressure,
and also the directions of spin for each of those are opposite in the
two hemispheres. That's why air circulates around low and high pressure
areas, and AFAIAA it's called the Coriolis effect not the Coriolis force
(or more strictly still '*a* Coriolis effect' because there are others,
such as dropping a rock from a high enough tower causes it to land
slightly ahead of directly under the point where it was dropped, because
initially it was travelling slightly faster through space and therefore
overtakes that point).

[NY]

"Java Jive" <ja...@evij.com.invalid> wrote in message
news:sv0cfu$2l5$1...@dont-email.me...

> (or more strictly still '*a* Coriolis effect' because there are others,
> such as dropping a rock from a high enough tower causes it to land
> slightly ahead of directly under the point where it was dropped, because
> initially it was travelling slightly faster through space and therefore
> overtakes that point).

Surely the lateral speed of the rock (relative to a stationary observer out
in space) remains the same as the earth's speed, no matter how much the rock
accelerates in a downward direction due to gravity and is decelerated by
speed-dependent slowing due to air resistance. Or to put it another way, the
rock remains stationary relative to the ground in a lateral direction.
That's assuming there's no wind - ie that the atmosphere is rotating at the
same speed as the earth and the tower.

Or am I about to learn something? Is the effect that you are describing one
that only exists because of the earth's atmosphere, or would it also be true
in a vacuum?

I imagine there *could* be "spinning cricket-ball" forces on the ball if it
rotates as it falls.

[Jim Lesurf]

In article <j7h751...@mid.individual.net>, Andy Burns

I find that very handy. It has been particularly useful for knowing what to
expect during the recent storms, and when the wind would be highest or the
temperature lowest. The level of detail specific to where we live is
welcome. Given that we are on the coast the details of what happens here
are often different from just a few miles inland. e.g. we get rain or dry
when a short way away they get snow!

Jim

--
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[Woody]

Clearly there are a lot of people on this group that <do> understand
weather and isobaric charts and thus probably the Shipping Forecast?

Slightly off line then could I recommend to those with such
understanding a book called 'Attention All Shipping' by Charlie
Connelly. He visits every SF area or at least as near as he can get to
them. Fascinating reading but just slightly tongue in cheek.

[Jim Lesurf]

In article <sv0cfu$2l5$1...@dont-email.me>, Java Jive <ja...@evij.com.invalid>
wrote:

> Yeah, sure, :-), but, still being pedantic, that's not why storms spin,
> which Brian has had a go at explaining elsewhere. AIUI, it should be
> called 'the Coriolis effect', because AFAIAA there are no actual forces
> involved, just differences in linear velocity at different latitudes on
> a rotating object such as the earth.

The use of 'fictional' for 'forces' is perhaps more of a lable indicating
"simplified explaination". After all Gravitation is a "fictional force"
when considering things in terms of GR. 8-]

Similarly for 'magnetic forces' which are because you're not in the rest
frame of electric chargest that 'cause' the "magnetic field".

Add in what QM does for 'distance' on top of what GR does for it, and the
result isn't what you get told in School. 8-]

[Jim Lesurf]

In article <sv0d73$824$1...@dont-email.me>, NY <m...@privacy.invalid> wrote:
> "Java Jive" <ja...@evij.com.invalid> wrote in message
> news:sv0cfu$2l5$1...@dont-email.me...
> > (or more strictly still '*a* Coriolis effect' because there are
> > others, such as dropping a rock from a high enough tower causes it to
> > land slightly ahead of directly under the point where it was dropped,
> > because initially it was travelling slightly faster through space and
> > therefore overtakes that point).

> Surely the lateral speed of the rock (relative to a stationary observer
> out in space) remains the same as the earth's speed, no matter how much
> the rock accelerates in a downward direction due to gravity and is
> decelerated by speed-dependent slowing due to air resistance.

In the frame that rotates with the Earth the horizontal velocity may seem
the same. But in a non-rotating frame the further you are from the center
of the Earth, the larger the velocity perpendicular to the radial line
though the center of rotation. Thus the tops of tall buildings are moving
faster than the ground floor as the circumference they have to travel in a
day is longer.

[Java Jive]

Well, I've never heard it called that, so my first reaction was to ask
myself: "I wonder if he's confusing it with the centrifugal force,
which, although it's just an inertial effect, is often called a
fictional force, because it has the same units as a real force?"

However, Wikipedia agrees with you, and even gives a formula for the
Coriolis effect, though unfortunately they don't show it's derivation.
For Applied Maths A-level, we did many, many examples of satellite
orbits, etc, so I'm very familiar with the term in the formula for the
centrifugal effect, which is m.v^2/r or m.r.omega^2, where omega=v/r,
but I've never seen the Coriolis effect treated as a fictional force before.

FTR, the formula they give for the Coriolis 'force' is ...
-2.m.v.omega or -2.m.v^2/r or -2.m.r.omega^2
... but vectors are involved - it's a cross-product - which is
difficult to convey here in simple ASCII text, but those interested can
take a look here:

https://en.wikipedia.org/wiki/Coriolis_force

[Java Jive]

On 21/02/2022 16:04, NY wrote:
>
> "Java Jive" <ja...@evij.com.invalid> wrote in message
> news:sv0cfu$2l5$1...@dont-email.me...
>>
>> (or more strictly still '*a* Coriolis effect' because there are
>> others, such as dropping a rock from a high enough tower causes it to
>> land slightly ahead of directly under the point where it was dropped,
>> because initially it was travelling slightly faster through space and
>> therefore overtakes that point).
>
> Surely the lateral speed of the rock (relative to a stationary observer
> out in space) remains the same as the earth's speed, no matter how much
> the rock accelerates in a downward direction due to gravity and is
> decelerated by speed-dependent slowing due to air resistance. Or to put
> it another way, the rock remains stationary relative to the ground in a
> lateral direction. That's assuming there's no wind - ie that the
> atmosphere is rotating at the same speed as the earth and the tower.

Theoretically, ignoring air-resistance, comparing the linear speeds of
the rock and the point on earth's surface directly underneath where it
is dropped from, the rock has a larger radius of spin around the earth's
axis by an amount equal to the height of the tower, therefore when it is
dropped its linear velocity in the direction of earth's spin is slightly
faster than the point on earth's surface directly underneath, so it will
land slightly ahead of it.

> Or am I about to learn something? Is the effect that you are describing
> one that only exists because of the earth's atmosphere, or would it also
> be true in a vacuum?

It would certainly be true in a vacuum, and also in air, but the
latter's resistance would reduce the effect, perhaps enough to make it
immeasurable.

But see also my other post where I admit that I've always called the
Coriolis effect is actually classed as a fictitious force, I'd just
never heard it called that before.

[charles]

In article <sv0eb9$h67$1...@dont-email.me>,

Heard a talk on Zoom - with pictures, by him during lockdown about this.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

[Robin]

On 21/02/2022 16:51, Java Jive wrote:

>
> But see also my other post where I admit that I've always called the
> Coriolis effect is actually classed as a fictitious force, I'd just
> never heard it called that before.
>

You may well have been using "the Coriolis effect" accurately. The 2
terms can co-exist amicably with the [fictitious] force explaining the
effect. And I /think/ making it easier to do sums in some practical
scenarios. (I certainly hope so as I couldn't now do sums with the
cross-vectors if me life depended on it. And the more advanced
equations of motion for a particle in a rotating frame but a distant
nightmare.)

[Andy Burns]

Jim Lesurf wrote:

> Andy Burns wrote:
>
>> the BBC weather app forecasts in 1 hour slots for 14
>> days ahead, which strikes me as an utterly pointless level of detail.
>
> I find that very handy.

9am tomorrow morning: good

9am in a couple of days time: not bad

but 9am on the sunday after next: fantasy weather.

[Jeff Layman]

Just below the coloured scale is something called "Control". Using >
goes forward an hour; using >> goes forward 8 hours. If you click on the
icon next to "Now" you can choose a date up to 4 days ahead. It's a
forecast of sorts, I suppose.

--

Jeff

[NY]

"Java Jive" <ja...@evij.com.invalid> wrote in message

news:sv0fuf$tgt$1...@dont-email.me...

> On 21/02/2022 16:04, NY wrote:
>>
>> "Java Jive" <ja...@evij.com.invalid> wrote in message
>> news:sv0cfu$2l5$1...@dont-email.me...
>>>
>>> (or more strictly still '*a* Coriolis effect' because there are others,
>>> such as dropping a rock from a high enough tower causes it to land
>>> slightly ahead of directly under the point where it was dropped, because
>>> initially it was travelling slightly faster through space and therefore
>>> overtakes that point).
>>
>> Surely the lateral speed of the rock (relative to a stationary observer
>> out in space) remains the same as the earth's speed, no matter how much
>> the rock accelerates in a downward direction due to gravity and is
>> decelerated by speed-dependent slowing due to air resistance. Or to put
>> it another way, the rock remains stationary relative to the ground in a
>> lateral direction. That's assuming there's no wind - ie that the
>> atmosphere is rotating at the same speed as the earth and the tower.
>
> Theoretically, ignoring air-resistance, comparing the linear speeds of the
> rock and the point on earth's surface directly underneath where it is
> dropped from, the rock has a larger radius of spin around the earth's axis
> by an amount equal to the height of the tower, therefore when it is
> dropped its linear velocity in the direction of earth's spin is slightly
> faster than the point on earth's surface directly underneath, so it will
> land slightly ahead of it.

Yeeeeeeeeees (he says, reluctantly!) you have a very good point there. But
wouldn't the motion of the falling rock be along a radius of the earth so
the rock would remain parallel to the building? Or is the slight error of
the two sides of the building being parallel rather than converging radii
enough to give a noticeable error in the landing position. As a matter of
interest, how large is the effect, in terms of horizontal displacement as a
function of building height?

I think I believe you, but in true "take nobody's word for it" scientific
tradition I'm going to have to test it to prove it to myself. Now where's
there a nice tall tower block that I can drop a stone off without any danger
of it hitting someone below?

[NY]

"Java Jive" <ja...@evij.com.invalid> wrote in message

news:sv0evm$m5c$1...@dont-email.me...

> Well, I've never heard it called that, so my first reaction was to ask
> myself: "I wonder if he's confusing it with the centrifugal force, which,
> although it's just an inertial effect, is often called a fictional force,
> because it has the same units as a real force?"

I was always confused when centrifugal force was described as fictional
because it can definitely be felt and demonstrated. If you tie a weight to a
piece of string and whirl it round your head, you can feel a force acting
outwards on your hand. If you attach a light weight to one end of the
string, thread it through a cotton reel as a "bearing" and attach a heavier
weight to the other end, the whirling light weight can cause the heavier
weight to rise, as if there was a force acting outwards on the whirling
weight and upwards (via the "bearing") on the heavy weight. I suppose it's
all to do with frame of reference: we tend to judge it wrt to the centre of
rotation as the frame of reference, rather than the FoR of a stationary
bystander.

Maybe it can all be waved away by saying the centrifugal force is a
fictional equal-and-opposite reaction to the very real and undisputed
centripetal force, such that the rotating object remains at a constant
radius rather than actually spiralling towards the centre as CP force on its
own would imply.

[Roderick Stewart]

I wonder how many of them could explain the working of log tables, or
a slide rule?

Rod.

[Ian Jackson]

In message <yN688cEs...@brattleho.plus.com>, Ian Jackson
<ianREMOVET...@g3ohx.co.uk> writes

>The BBC have introduced a new, improved style of presenting the weather.
>
>On their website, there no longer appears to be a proper 'Jack Scott'
>weather map (Surface Pressure Chart), as per
><https://www.metoffice.gov.uk/public/weather/surface-pressure/#?tab=surfa
>cePressureColour&fcTime=1517918400>
>
>Is it there somewhere, and I can't find it - or do the BBC feel that
>nobody was interested?

It's amazing how much interest has been generated by something I posted
in February 2018!!!
--
Ian

[Jim Lesurf]

In article <sv1413$tcq$1...@dont-email.me>, NY <m...@privacy.invalid> wrote:
> I was always confused when centrifugal force was described as fictional
> because it can definitely be felt and demonstrated. If you tie a weight
> to a piece of string and whirl it round your head, you can feel a force
> acting outwards on your hand.

Newton's Laws state that a moving item will - if left to itself - travel in
a straight line. The force *you* apply via the string makes it go round in
a circle. Stop applying that force are it will no longer circle you.

[Sn!pe]

Jim Lesurf <no...@audiomisc.co.uk> wrote:

> In article <sv1413$tcq$1...@dont-email.me>, NY <m...@privacy.invalid> wrote:
> > I was always confused when centrifugal force was described as fictional
> > because it can definitely be felt and demonstrated. If you tie a weight
> > to a piece of string and whirl it round your head, you can feel a force
> > acting outwards on your hand.
>
> Newton's Laws state that a moving item will - if left to itself - travel in
> a straight line. The force *you* apply via the string makes it go round in
> a circle. Stop applying that force are it will no longer circle you.
>
> Jim
>

<https://www.physicsclassroom.com/class/newtlaws/Lesson-4/Newton-s-Third-Law>

Newton's Third Law

"For every action, there is an equal and opposite reaction."

"The statement means that in every interaction, there is a pair of
forces acting on the two interacting objects. The size of the forces on
the first object equals the size of the force on the second object. The
direction of the force on the first object is opposite to the direction
of the force on the second object. Forces always come in pairs - equal
and opposite action-reaction force pairs."

Q: If centripetal force is real, what is its Third Law counterpart?
Is it real?

--
^Ï^ <https://youtu.be/_kqytf31a8E>

My pet rock Gordon just is.

[Robin]

When you whirl the string around there are 2 forces*. One is the string
pulling the object. The other is the string pulling you. They are
equal and opposite.

*from the tension in the string. Let's leave aside gravity, air
resistance, interaction of damp string with the earth's magnetic field,
the effects of last night's curry, ...

[Sn!pe]

Therefore 'Centrifugal Force' is real, not imaginary. QED

>
> Let's leave aside gravity, air resistance, interaction of damp string with
> the earth's magnetic field, the effects of last night's curry, ...
>

Oh, gladly. I would not want to inflict last night's curry on anybody.

--
^Ď^ <https://youtu.be/_kqytf31a8E>

[Robin]

Neither of the 2 forces above is the mythical "centrifugal force". See
the site you quoted above:

https://www.physicsclassroom.com/class/circles/Lesson-1/The-Forbidden-F-Word

[Sn!pe]

Granted. So what, then, is the force experienced by a finger
whirling a weighty object around on a string? The force is
undeniably transmitted by the string, but what is its name?

--
^Ï^ <https://youtu.be/_kqytf31a8E>

[Robin]

On 22/02/2022 17:06, Sn!pe wrote:

>
> So what, then, is the force experienced by a finger
> whirling a weighty object around on a string? The force is
> undeniably transmitted by the string, but what is its name?
>

How about "the force on your finger that's keeping the weighty object
whirling around on a string rather than flying off in a straight line at
a tangent"?

[Sn!pe]

Robin <r...@outlook.com> wrote:

> On 22/02/2022 17:06, Sn!pe wrote:
>
> >
> > So what, then, is the force experienced by a finger
> > whirling a weighty object around on a string? The force is
> > undeniably transmitted by the string, but what is its name?
> >
>
> How about "the force on your finger that's keeping the weighty object
> whirling around on a string rather than flying off in a straight line at
> a tangent"?
>

If we set our minds to it I'm sure we could think of something
better than that. How about "centrifugal force"?

[Robin]

On 22/02/2022 18:21, Sn!pe wrote:
> Robin <r...@outlook.com> wrote:
>
>> On 22/02/2022 17:06, Sn!pe wrote:
>>
>>>
>>> So what, then, is the force experienced by a finger
>>> whirling a weighty object around on a string? The force is
>>> undeniably transmitted by the string, but what is its name?
>>>
>>
>> How about "the force on your finger that's keeping the weighty object
>> whirling around on a string rather than flying off in a straight line at
>> a tangent"?
>>
>
> If we set our minds to it I'm sure we could think of something
> better than that. How about "centrifugal force"?
>

I've already told you the "centrifugal force" ain't real. I don't think
I can help you further.

[NY]

"Jim Lesurf" <no...@audiomisc.co.uk> wrote in message
news:59beb0d...@audiomisc.co.uk...

> In article <sv1413$tcq$1...@dont-email.me>, NY <m...@privacy.invalid> wrote:
>> I was always confused when centrifugal force was described as fictional
>> because it can definitely be felt and demonstrated. If you tie a weight
>> to a piece of string and whirl it round your head, you can feel a force
>> acting outwards on your hand.
>
> Newton's Laws state that a moving item will - if left to itself - travel
> in
> a straight line. The force *you* apply via the string makes it go round in
> a circle. Stop applying that force are it will no longer circle you.

Sure. And what name to you give to the outward (away from the centre) force
that I experience while swinging the stone around my head, or the one which
causes a light rotating weight to lift up a heavier one on the other end of
the string? Physics needs to acknowledge these, rather than trying to
pretend they don't exist.

[NY]

"Robin" <r...@outlook.com> wrote in message
news:7dc991c1-c662-483b...@outlook.com...

You can *say* that it isn't real, but everyday experience would disagree
with you. Just because someone says that black is really white doesn't
automatically make it so.

[Sn!pe]

Robin <r...@outlook.com> wrote:

> On 22/02/2022 18:21, Sn!pe wrote:
> > Robin <r...@outlook.com> wrote:
> >
> >> On 22/02/2022 17:06, Sn!pe wrote:
> >>
> >>>
> >>> So what, then, is the force experienced by a finger
> >>> whirling a weighty object around on a string? The force is
> >>> undeniably transmitted by the string, but what is its name?
> >>>
> >>
> >> How about "the force on your finger that's keeping the weighty object
> >> whirling around on a string rather than flying off in a straight line at
> >> a tangent"?
> >>
> >
> > If we set our minds to it I'm sure we could think of something
> > better than that. How about "centrifugal force"?
> >
>
> I've already told you the "centrifugal force" ain't real. I don't think
> I can help you further.
>

Is there not a capacity to do work provided by the imaginary
centrifugal/centripetal force transmitted down the string?
Is that work imaginary? Surely if the work is real, the force
must likewise be real.

--
^Ď^ <https://youtu.be/_kqytf31a8E>

[Indy Jess John]

On 22/02/2022 22:16, NY wrote:

> You can *say* that it isn't real, but everyday experience would disagree
> with you. Just because someone says that black is really white doesn't
> automatically make it so.
>

<grin>

It depends on the dictionary.

One synonym of Black is Dark
One synonym of Dark is Dim
One synonym of Dim is Pale
One synonym of Pale is Light
One synonym of Light is Bright
One synonym of Bright is White

QED :-)

Jim

[Jeff Layman]

Perhaps it'll turn out to be something like Laithwaite's examination of
gyroscopes.

--

Jeff

[BrightsideS9]

Satellites in orbit maintain their distance from earth by traveling at
velocity that ensures that the force of gravity towards the earth does
not lower the orbit. There is only that one force, gravity, towards
the earth. Explanation for 11 to 14 years old here:-

https://spark.iop.org/how-do-satellites-stay-orbit

Your misunderstanding should not make it a necessity for physics to
acknowledge non existent forces? Do you still believe in witchcraft?

--
brightside S9

[Roderick Stewart]

On Tue, 22 Feb 2022 20:08:17 +0000, Robin <r...@outlook.com> wrote:

>> If we set our minds to it I'm sure we could think of something
>> better than that. How about "centrifugal force"?
>>
>
>I've already told you the "centrifugal force" ain't real. I don't think
>I can help you further.

What about "centrifugal reaction"? The centripetal force, whether
we're talking about interplanetary gravity or string, is a real force
applied at right angles to the straight line the object would follow
if it was left alone. The object's inertial reluctance to follow the
force is a reaction to it that feels like an outward force to whoever
or whatever is actually applying the inward one.

The fact that the force is at right angles to the direction of travel
of the object and thus neither speeding it up nor slowing it down
means that no energy is being added or subtracted because no mass is
being moved in the direction of any force, which is why in the absence
of any other forces the rotation could continue forever.

It's not rocket science...

Rod.

[Jim Lesurf]

In article <1pns8gn.mmya1e1lt358dN%snip...@gmail.com>, Sn!pe

<snip...@gmail.com> wrote:
> Newton's Third Law

> "For every action, there is an equal and opposite reaction."

> "The statement means that in every interaction, there is a pair of
> forces acting on the two interacting objects. The size of the forces on
> the first object equals the size of the force on the second object. The
> direction of the force on the first object is opposite to the direction
> of the force on the second object. Forces always come in pairs - equal
> and opposite action-reaction force pairs."

> Q: If centripetal force is real, what is its Third Law counterpart? Is
> it real?

You (and the Earth you're standing on) will also orbit around the common
center of mass of you + earth + object on the other end of the string.

You may not notice that the Earth is being moved, though, as it tends to be
somewhat larger in mass than anything you whirl around on a bit of string!
:-)

However if you consider a sub-part of the system what you see is
accelleration. In this case the object you whirl round is being
accellerated towards the center of its rotation, so goes around you.

[Max Demian]

On 22/02/2022 22:16, NY wrote:

What about suction? A vacuum doesn't suck. A vacuum isn't anything, so
how can it suck?

Things *seem* to be hard, though, in fact, they are made of atoms which
are mostly empty space. They seem to be hard due to the electrostatic
repulsion between their electron fields.

--
Max Demian

[Indy Jess John]

It took me a while to find this, but here it is for anyone interested.
https://www.rigb.org/explore-science/explore/video/engineer-through-looking-glass-jabberwock-1974

Jim

[Jeff Layman]

I'll have a look at that later. Oddly enough, Ref 4 on the Wiki page
about Laithwaite is for that lecture, but leads to a "not found" at the
RIGB website. However, search for "looking glass" on that page, and it
turns up that, and the other Christmas lectures, by Laithwaite.

The Wiki page notes that "Laithwaite later acknowledged that gyroscopes
behave fully in accord with Newtonian mechanics". It adds, however, "To
this very day, research is conducted to account for the physics behind
gyroscopic effects, directly pointing to Laithwaite's work as
motivation." See
<https://iopscience.iop.org/article/10.1088/1361-6404/abce88/meta>.

--

Jeff

[Jeff Layman]

OT, really, but perhaps you know something about this area. I've often
wondered about the physical characteristics of elements - their hardness
(in the solid state. How hard is solid Oxygen?!), their MP and BP, and
their density. Exactly what determines these, and can physics predict
what these values of an element would be?

--

Jeff

[Java Jive]

LOL!

--

Fake news kills!

I may be contacted via the contact address given on my website:
www.macfh.co.uk

[NY]

"Roderick Stewart" <rj...@escapetime.myzen.co.uk> wrote in message
news:5ovb1h1ihspn90lh3...@4ax.com...

If you work in a chemistry lab, you may want to separate a solid precipitate
from a liquid in which it is is suspended. You do this by placing a test
tube of it in a device like a small spin-drier which rotates it at very high
speed so the bottom of the test tube spins outwards while the neck of the
tube is held in place in the rotating mechanism. A force causes the
precipitate to gather at the bottom of the tube.

This device is called a centrifuge. Is it a misnomer? Should it be called a
centripete? Did early scientists make a mistake with their physics when they
were naming the device?


My impression is that centrifugal force was taught in schools until I
changed from a traditional public school which taught a very traditional
syllabus to a grammar school which taught a more progressive Nuffield
science syllabus - so for me the change occurred in the mid 1970s. Is that
other people's experience: that "centrifugal" force/reaction/effect became
banned phrases in the mid 1970s? Or have some of you who are older than me
been taught "centrifugal bad, centripetal good" from long before this time?
Without the word "centrifugal" you have to resort to very long-winded,
roundabout phrases to describe the "force" that people *think* they
experience when they are spinning round on a roundabout and have to hold on
to prevent them being flung *away* from the centre. I remember my physics
teacher getting really exasperated with us when we resorted to all the
circumlocutions to avoid "centripetal" and yelling at us "but doesn't matter
*how* you describe it - it DOES NOT EXIST". But he could not explain to
anyone's satisfaction why everyone *thinks* there is a force that acts away
from the centre.

I think the problem is that when you are on the child's roundabout, your
frame of reference effectively places your "straight ahead" direction (ie at
right angles to the radius) on a curve. We are used to straight ahead being
a straight line rather than a constant-radius curve, and try to apply
terminology from a straight-line frame of reference to this unusual one
where "straight ahead" is a curve. There is also the problem that in normal,
non-scientific use of the word, "accelerate" implies a change in speed
(linear or rotational), whereas physics uses the word to describe a change
in velocity - ie a change in either/both of speed and direction. Thus you
can be accelerating constantly towards the centre of the circle while
manifestly travelling at a constant scalar speed, either in terms of linear
metres/second or in rotational degrees/second.


The other shock to the system in changing from a traditional to a modern
physics course was that "per" quantities (metres per second, radians per
hour, furlongs per fortnight) must be expressed using negative-exponent
terminology, rather than with the use of the / to denote division. "m/sec"
can be read as metres per second. But how should you read m s^-1 (where ^-1
denotes a superscript -1)? Anyone who wrote m/s or kg/m^3 was liable to
incur the physics teacher's wrath. His nickname (inevitably) was "Canute"
because he was trying to argue against something that was just too deeply
ingrained into general English language to be changed at the whim of a new
science syllabus. Similarly, our chemistry teacher, bless her, tried so hard
when she was teaching us organic chemistry to use IUPAC names (ethanoic
acid), but even *she* sometimes forgot herself and referred to "acetic
acid". Sometimes logic and consistency has to take a back seat to common
parlance that people have grown up with.

[Robin]

On 23/02/2022 12:04, Indy Jess John wrote:

>> Perhaps it'll turn out to -be something like Laithwaite's examination of

>> gyroscopes.
>>
>
> It took me a while to find this, but here it is for anyone interested.
> https://www.rigb.org/explore-science/explore/video/engineer-through-looking-glass-jabberwock-1974
>
>

I was still at university at the time of his infamous Christmas lecture
and remember well the outrage (tinged with pity for the death of his
academic reputation). He ignored the way calculations using no more than
Newton's laws explained the way the gyroscopes behaved. Apparently just
didn't want to believe those who could do the sums.

[Indy Jess John]

Given that Einstein showed that Newton's Laws didn't cover all possible
circumstances, it was a bit unfair to pillory Laithwaite for suggesting
the same thing.

Science is supposed to welcome challenges to established beliefs, yet
the Royal Institution took the unprecedented decision of banning the TV
broadcast of that set of Christmas Lectures without even considering the
ideas put forward.

As some one who attended two Christmas Lectures (in the 1960s on
Radioactivity and Cryogenics) I know that they inspire curiosity rather
than taking everything I heard as all there is to know. Laithwaite
would have had a similar effect on his audiences.

Jim

[Robin]

Your comparison is fatally flawed. One last time: Laithwaite's evidence
not only could be explained by Newton's laws but had been before the
lectures.

> Science is supposed to welcome challenges to established beliefs, yet
> the Royal Institution took the unprecedented decision of banning the TV
> broadcast of that set of Christmas Lectures without even considering the
> ideas put forward.

Eh? The lectures were broadcast.

[NY]

"Indy Jess John" <bathwa...@OMITTHISgooglemail.com> wrote in message
news:sv5i0p$r75$1...@dont-email.me...

> Science is supposed to welcome challenges to established beliefs, yet the
> Royal Institution took the unprecedented decision of banning the TV
> broadcast of that set of Christmas Lectures without even considering the
> ideas put forward.

Did they? I thought I'd seen Laithwaite expounding his theories on
gyroscopes. The RI was very wrong if it censored him by banning the
broadcast after it had been recorded. There must have been some very hasty
meetings after the first couple, because the lead time between recording and
broadcast is (or certainly was in the late 1970s) only a few days: I'm sure
they were broadcasting the first one on or before the day that I attended
the last one - that was for Erik Zeeman in 78 and Eric Rogers in 79. Rogers
cocked up the bromine diffusion experiment badly, and spilled bromine liquid
on the hands of long-suffering RI assistant Eric Coates who was heard to
mutter a few choice words under his breath (*), though the camera didn't see
the grimace of pain on his face. There was a long break while Coates had his
fingers washed, treated and bandaged, and while the baize on the table was
replaced (by baize of a *different* colour!). Recording then resumed, but
the join in the recording that was broadcast was rather obvious because the
baize suddenly changed between one shot an the next from green to beige, and
Eric Coates's fingers suddenly acquired bandages. I imagine the recording of
the original attempt has been included in a few VT engineers' Christmas
compilation tapes ;-)


(*) I bet they wished they hadn't miked-up him as well as the lecturer ;-)

[Max Demian]

I'm not by any means an expert (!), but maybe liquid and gas forms of
atoms are just as hard as solids, but the molecules dodge about a lot!

I don't think that physics (actually physical chemistry) can accurately
predict the properties of the elements, so chemists roughly predict them
from their position in the Periodic Table, and relation to other elements.

--
Max Demian

[Max Demian]

On 23/02/2022 13:48, NY wrote:
> "Roderick Stewart" <rj...@escapetime.myzen.co.uk> wrote in message
> news:5ovb1h1ihspn90lh3...@4ax.com...
>> On Tue, 22 Feb 2022 20:08:17 +0000, Robin <r...@outlook.com> wrote:

>>> I've already told you the "centrifugal force" ain't real. I don't think
>>> I can help you further.

> If you work in a chemistry lab, you may want to separate a solid
> precipitate from a liquid in which it is is suspended. You do this by
> placing a test tube of it in a device like a small spin-drier which
> rotates it at very high speed so the bottom of the test tube spins
> outwards while the neck of the tube is held in place in the rotating
> mechanism. A force causes the precipitate to gather at the bottom of the
> tube.
>
> This device is called a centrifuge. Is it a misnomer? Should it be
> called a centripete? Did early scientists make a mistake with their
> physics when they were naming the device?

Scientist are always naming things wrongly. "Atoms" should be impossible
to cut: that's what the Greek means, as was hypothesised by the
Ancients. If they were more pedantic, they would never have split the
atom to make atom bombs and generate nuclear (fission) power as it is
etymologically impossible to split the atom. Perhaps they should have
waited for quarks to be discovered and named them atoms.

--
Max Demian

[Jeff Layman]

It gets even more confusing when isotopes are considered - hydrogen,
deuterium, and tritium, have a different MP and BP. I'd be interested to
know if any physicists have ever considered looking at physical
properties of elements in respect of their atomic structure and bonding
(I very much doubt it!).

--

Jeff

[williamwright]

On 22/02/2022 23:22, Indy Jess John wrote:

No, far too convoluted.
White is black when you turn the light out.
If white is black then black is white.
Simple.
Bill

[Roderick Stewart]

On Wed, 23 Feb 2022 13:48:29 -0000, "NY" <m...@privacy.invalid> wrote:

>If you work in a chemistry lab, you may want to separate a solid precipitate
>from a liquid in which it is is suspended. You do this by placing a test
>tube of it in a device like a small spin-drier which rotates it at very high
>speed so the bottom of the test tube spins outwards while the neck of the
>tube is held in place in the rotating mechanism. A force causes the
>precipitate to gather at the bottom of the tube.
>
>This device is called a centrifuge. Is it a misnomer? Should it be called a
>centripete? Did early scientists make a mistake with their physics when they
>were naming the device?

Maybe they did. It wouldn't be the first time. They got electric
current the wrong way round after all, and by the time the truth was
discovered it was too late to rewrite all the textbooks.

There are lots of things that are or were called the wrong things, and
sometimes changed later in an attempt to reduce confusion, sometimes
successfully and sometimes just causing more. For example, "superhet"
circuitry is from "supersonic heterodyne" because supersonic used to
mean having a higher frequency than we can hear. Then there's the
"drop-frame" method of recording TV signals on film, though it
actually drops fields, because the meanings of those words has
changed, and then there's the requirement to buy a licence to watch
"live" television, which usually isn't live at all in the sense that
I've always understood it. I'm sure you csn think of more examples.

Rod.

[David Woolley]

On 23/02/2022 09:41, BrightsideS9 wrote:
> There is only that one force, gravity, towards
> the earth.

There is equal gravity pulling the satellite towards the earth. Whilst
this doesn't have much effect for current artificial satellites, it is
very significant for our natural satellite, leading to tides.

The effect is that the moon swings the earth around with a radius of
about 4,700km

[williamwright]

On 23/02/2022 20:39, Roderick Stewart wrote:
> Maybe they did. It wouldn't be the first time. They got electric
> current the wrong way round after all, and by the time the truth was
> discovered it was too late to rewrite all the textbooks.
>
> There are lots of things that are or were called the wrong things, and
> sometimes changed later in an attempt to reduce confusion, sometimes
> successfully and sometimes just causing more. For example, "superhet"
> circuitry is from "supersonic heterodyne" because supersonic used to
> mean having a higher frequency than we can hear. Then there's the
> "drop-frame" method of recording TV signals on film, though it
> actually drops fields, because the meanings of those words has
> changed, and then there's the requirement to buy a licence to watch
> "live" television, which usually isn't live at all in the sense that
> I've always understood it. I'm sure you csn think of more examples.
>
> Rod.

MOT certificate

Bill

[Indy Jess John]

On 23/02/2022 16:13, NY wrote:
> Did they? I thought I'd seen Laithwaite expounding his theories on
> gyroscopes. The RI was very wrong if it censored him by banning the
> broadcast after it had been recorded.

One of the things I found while hunting for the gyroscope lecture said
that the lectures were not broadcast *at the scheduled time*, but there
was no mention of when it was actually broadcast. You probably saw it
when it was broadcast later.

I can't comment on that at first hand because in the 1970s I was in a
flat with no TV.

Jim

[NY]

"Indy Jess John" <bathwa...@OMITTHISgooglemail.com> wrote in message

news:sv7j4b$vrv$1...@dont-email.me...

> On 23/02/2022 16:13, NY wrote:
>> Did they? I thought I'd seen Laithwaite expounding his theories on
>> gyroscopes. The RI was very wrong if it censored him by banning the
>> broadcast after it had been recorded.
>
> One of the things I found while hunting for the gyroscope lecture said
> that the lectures were not broadcast *at the scheduled time*, but there
> was no mention of when it was actually broadcast. You probably saw it
> when it was broadcast later.

Was it the Laithwaite RI lectures where one of them ended with him using an
electric drill to spin a heavy flywheel that was attached to a rope hanging
from the ceiling, and it did all the counter-intuitive things (to oohs and
ahs from the audience) that you get with gyroscopes? Or was that another
demonstration, separate from the RI lectures?


Looking at the BBC Genome (Radio Times listings) site, it seems that
Laithwaite's 1967 lectures "The Engineer in Wonderland" was broadcast in
July rather than December/January. The 1974 lectures "The Engineer Through
the Looking Glass" were broadcast from 29 Dec 74 to 3 Jan 75, with the
gyroscope lecture being on 1 Jan 75. Those are all published scheduled
times - whether there was a last-minute replacement is another matter ;-)
Interestingly the 1974 lectures were repeated 17-24 December 1975 - just
before the first broadcast of the 1975 Heinz Wolff lectures: it seems that
they tended to repeat the previous lectures in early December a few days
before the current year's lectures were show for the first time.

[Jim Lesurf]

In article <sv5a8u$pne$1...@dont-email.me>, Jeff Layman

<jmla...@invalid.invalid> wrote:
> > https://www.rigb.org/explore-science/explore/video/engineer-through-looking-glass-jabberwock-1974

> I'll have a look at that later. Oddly enough, Ref 4 on the Wiki page
> about Laithwaite is for that lecture, but leads to a "not found" at the
> RIGB website. However, search for "looking glass" on that page, and it
> turns up that, and the other Christmas lectures, by Laithwaite.

The page shows here on a lite browser some black rectangles where video
access might be expected and a message saying I have been "banned
permanently! With an link to 'vimeo'. Who I've never used so far as I know.
Weird! Maybe yt-dlp can make sense of it?

> The Wiki page notes that "Laithwaite later acknowledged that gyroscopes
> behave fully in accord with Newtonian mechanics". It adds, however, "To
> this very day, research is conducted to account for the physics behind
> gyroscopic effects, directly pointing to Laithwaite's work as
> motivation." See
> <https://iopscience.iop.org/article/10.1088/1361-6404/abce88/meta>.

[Robin]

The lecture was broadcast in January 1975. There were e.g. responses
explaining how Newton suffices in New Scientist the following week.

[Indy Jess John]

On 23/02/2022 18:10, Jim Lesurf wrote:
> In article<sv5a8u$pne$1...@dont-email.me>, Jeff Layman
> <jmla...@invalid.invalid> wrote:
>>> https://www.rigb.org/explore-science/explore/video/engineer-through-looking-glass-jabberwock-1974
>
>> I'll have a look at that later. Oddly enough, Ref 4 on the Wiki page
>> about Laithwaite is for that lecture, but leads to a "not found" at the
>> RIGB website. However, search for "looking glass" on that page, and it
>> turns up that, and the other Christmas lectures, by Laithwaite.
>
> The page shows here on a lite browser some black rectangles where video
> access might be expected and a message saying I have been "banned
> permanently! With an link to 'vimeo'. Who I've never used so far as I know.
> Weird! Maybe yt-dlp can make sense of it?

I tried the link with Firefox, and it told me that the site was blocked
due to a previous incident (long reference given).
I was given the option of unblocking but first I had to prove by
completing a Captcha that I wasn't a robot, which I did.

I then got access to the Abstract, but was told I had to register to
join in order to read the full article. I didn't.

But I did copy the Abstract to paste into this message:
ABSTRACT
The forced precession of a symmetrical gyroscope is studied for the
particular case in which the axle of a flywheel is pivoted by a hinge
joint and follows a horizontal circular path of a given radius. The
aforementioned setup appears in the so-called Laithwaite engine, the
detailed mechanics of which are still an enigma. Instead of applying
Lagrangian equations, Newton's second law is applied to the rotating
gyroscope with respect to its center of mass. Three novel Euler
equations are developed that are much longer than those found in
textbooks. In this mechanical system, which is characterized by one
degree of freedom, the main nonlinear governing equation is identified
and then MATLAB code is developed to obtain and visualize the numerical
solution. Under particular conditions that ensure small oscillations of
the gyroscope's axle (a maximum oscillation of eight degrees in the lean
angle) near the horizontal plane through the pivot, a linearization is
performed and is successfully compared with the aforementioned nonlinear
numerical solution. The computer program facilitates the understanding
and calculation of physical quantities such as the internal forces and
moments, support forces and power transmission from the drive motor. In
particular, it is shown that, for a hinge joint, the period of
oscillation differs from that of a rotating pivot, which is crucial to
the debate about whether such an engine may produce a net thrust, or
not. A relevant paradox is resolved.

Yours, for what it is worth.

Jim

[Jim Lesurf]

In article <sv61oo$elu$1...@dont-email.me>, Jeff Layman

<jmla...@invalid.invalid> wrote:
> It gets even more confusing when isotopes are considered - hydrogen,
> deuterium, and tritium, have a different MP and BP. I'd be interested to
> know if any physicists have ever considered looking at physical
> properties of elements in respect of their atomic structure and bonding
> (I very much doubt it!).

Materials Scientists certainly do look into these things to understand and
predict them. One of my mates at QMC (as was) got into such areas of
research. But it isn't one I know so can't comment on details.

[Jim Lesurf]

In article <sv7v7m$tsj$1...@dont-email.me>, Indy Jess John

Thanks. Reminds me of the old "Dean Machine" that was claimed to violate
Newton's Laws or add a new 'Law'. And the mysterious system that A Bretram
Chandler dreamed up of 'spinning Mobeus Strips' that caused 'Time
Precession' to allow FTL in the old 'Grimes' SF series of 'sea stories in
space'. The stories and good simple entertainment, but the 'science' is
baffflegab, of course. :-)