On 23/02/2022 08:27, Jeff Layman wrote:
> On 22/02/2022 22:13, NY wrote:
>> "Jim Lesurf"<noise@audiomisc.co.uk> wrote in message
>> news:59beb0d629noise@audiomisc.co.uk...
>>> In article<sv1413$tcq$1@dont-email.me>, NY<me@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.
>
> 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

Jim

On 23/02/2022 12:04, Indy Jess John wrote:
> On 23/02/2022 08:27, Jeff Layman wrote:
>> On 22/02/2022 22:13, NY wrote:
>>> "Jim Lesurf"<noise@audiomisc.co.uk> wrote in message
>>> news:59beb0d629noise@audiomisc.co.uk...
>>>> In article<sv1413$tcq$1@dont-email.me>, NY<me@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.
>>
>> 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'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

On 23/02/2022 11:40, Max Demian wrote:
> On 22/02/2022 22:16, NY wrote:
>> "Robin" <rbw@outlook.com> wrote in message
>> news:7dc991c1-c662-483b-ff15-c208d9af361b@outlook.com...
>>> On 22/02/2022 18:21, Sn!pe 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.
>>
>> 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.
>
> 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.

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

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

LOL!

--

Fake news kills!

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

"Roderick Stewart" <rjfs@escapetime.myzen.co.uk> wrote in message
news:5ovb1h1ihspn90lh3ak555tieakat8mlnc@4ax.com...
> On Tue, 22 Feb 2022 20:08:17 +0000, Robin <rbw@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...

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.

On 23/02/2022 12:04, Indy Jess John wrote:
> On 23/02/2022 08:27, Jeff Layman wrote:
>> On 22/02/2022 22:13, NY wrote:
>>> "Jim Lesurf"<noise@audiomisc.co.uk>  wrote in message
>>> news:59beb0d629noise@audiomisc.co.uk...
>>>> In article<sv1413$tcq$1@dont-email.me>, NY<me@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.
>>
>> 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.

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

On 23/02/2022 14:01, Robin wrote:
> On 23/02/2022 12:04, Indy Jess John wrote:
>> On 23/02/2022 08:27, Jeff Layman wrote:
>>> On 22/02/2022 22:13, NY wrote:
>>>> "Jim Lesurf"<noise@audiomisc.co.uk> wrote in message
>>>> news:59beb0d629noise@audiomisc.co.uk...
>>>>> In article<sv1413$tcq$1@dont-email.me>, NY<me@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.
>>>
>>> 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.
>
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

On 23/02/2022 14:57, Indy Jess John wrote:
> On 23/02/2022 14:01, Robin wrote:
>> On 23/02/2022 12:04, Indy Jess John wrote:
>>> On 23/02/2022 08:27, Jeff Layman wrote:
>>>> On 22/02/2022 22:13, NY wrote:
>>>>> "Jim Lesurf"<noise@audiomisc.co.uk>   wrote in message
>>>>> news:59beb0d629noise@audiomisc.co.uk...
>>>>>> In article<sv1413$tcq$1@dont-email.me>, NY<me@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.
>>>>
>>>> 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.
>>
> 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.

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.

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

"Indy Jess John" <bathwatchdog@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 ;-)

On 23/02/2022 12:50, Jeff Layman wrote:
> On 23/02/2022 11:40, Max Demian wrote:

>> 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.
>
> 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?

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

On 23/02/2022 13:48, NY wrote:
> "Roderick Stewart" <rjfs@escapetime.myzen.co.uk> wrote in message
> news:5ovb1h1ihspn90lh3ak555tieakat8mlnc@4ax.com...
>> On Tue, 22 Feb 2022 20:08:17 +0000, Robin <rbw@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

On 23/02/2022 17:36, Max Demian wrote:
> On 23/02/2022 12:50, Jeff Layman wrote:
>> On 23/02/2022 11:40, Max Demian wrote:
>
>>> 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.
>>
>> 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?
>
> 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.

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

On 22/02/2022 23:22, Indy Jess John wrote:
> 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
>
No, far too convoluted.
White is black when you turn the light out.
If white is black then black is white.
Simple.
Bill

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

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

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

"Indy Jess John" <bathwatchdog@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.

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

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics https://www.st-andrews.ac.uk/~www_pa/Scots_Guide/intro/electron.htm
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On 24/02/2022 09:28, Indy Jess John wrote:
> 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.
>

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

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

On 23/02/2022 18:10, Jim Lesurf wrote:
> In article<sv5a8u$pne$1@dont-email.me>, Jeff Layman
> <jmlayman@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

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

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In article <sv7v7m$tsj$1@dont-email.me>, Indy Jess John
<bathwatchdog@OMITTHISgooglemail.com> wrote:

> 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.

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. :-)

Jim

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