Brass band on train demonstrates Doppler effect

[Adlington]

I'm a physicist by education (though non-practising for many years....), so I found this an interesting item to watch/listen to:

The Doppler effect causes shifts in wavelengths of sound and light, and is a major factor in demonstrating the existence of an ever-expanding universe. The theory inherited its name from the Austrian physicist Christian Doppler who first proposed the theory in 1842. It was a Dutch mathematician, Christoph Hendrik Diederik Buys Ballot, who successfully proved Christian Doppler's theory using brass musicians and a steam train in 1845.

At a Loughborough railway station, with the help of the Great Central Railway and the Hathern Brass Band, conductor Charles Hazlewood recreates the famous experiment.

BTW, the C.H.D. Buys Ballot's experiment used a train on the Utrecht-Amsterdam line.

 

[Cowley]

I listened to the program on iplayer radio the other day and really enjoyed it. Something a bit unusual.

 

[work-traveller]

I happened to catch that at the time of broadcast on Radio 4. I've occasionally thought that if I was hypothetically restricted to one media channel for the rest of my natural, I'd select BBC R4 - for the broadest range of programming, some of the best quality and most intelligent output.

 

[ASharpe]

A few years ago I was out walking near Guildford (I think out by Wood Street), at a foot crossing a diver sounded the horn rather close to the crossing. Due to the combination of perfect timing between the two tones and speed of the train the difference in tone was huge.

In my previous job as a physics teacher the effect needed little introduction as many pupils had noticed it before with sirens on emergency vehicles or when a car with a loud engine speed past. I find it hard to imagine how it must have been for someone to predict the effect and then demonstrate it.

 

[PaxVobiscum]

Rather fun!

Of course, and before anyone else points it out:

[pedant]it's not a really G we heard, its a G (in several different octaves) for Bb instruments (which is most of the ones we see) i.e. an F at concert pitch, and if that's a soprano cornet 4th from the left, he (like the Eb Bass) was actually playing a D not a G

One simply must speak up on behalf of those who are the bores on RailUK and like to mention such things.

 

[GusB]

In my previous job as a physics teacher the effect needed little introduction as many pupils had noticed it before with sirens on emergency vehicles or when a car with a loud engine speed past. I find it hard to imagine how it must have been for someone to predict the effect and then demonstrate it.

It was much more noticeable with the old two-tone emergency sirens than with the modern ones.

Rather fun!

Of course, and before anyone else points it out:

[pedant]it's not a really G we heard, its a G (in several different octaves) for Bb instruments (which is most of the ones we see) i.e. an F at concert pitch, and if that's a soprano cornet 4th from the left, he (like the Eb Bass) was actually playing a D not a G

One simply must speak up on behalf of those who are the bores on RailUK and like to mention such things.

Our schools' brass band also had French horns (not a traditional brass band instrument) and they were in F, which further complicated matters.

 

[Scotty]

The Doppler effect is easy to demonstrate on a train, when you go through a level crossing.

 

[DerekC]

A few years ago I was out walking near Guildford (I think out by Wood Street), at a foot crossing a diver sounded the horn rather close to the crossing.

I guess that the Wood Street crossing is close to the river, then.

 

[HSTFan57]

Slightly confusingly, it seems that distance alone can sometimes alter the perceived pitch of musical instruments, an effect that off-stage trumpeters are aware of:
https://brendanball.com/2012/02/09/the-offstage-trumpeter/
https://en.wikipedia.org/wiki/Offstage_instrument_or_choir_part_in_classical_music

 

[Master29]

A few years ago I was out walking near Guildford (I think out by Wood Street), at a foot crossing a diver sounded the horn rather close to the crossing. Due to the combination of perfect timing between the two tones and speed of the train the difference in tone was huge.

In my previous job as a physics teacher the effect needed little introduction as many pupils had noticed it before with sirens on emergency vehicles or when a car with a loud engine speed past. I find it hard to imagine how it must have been for someone to predict the effect and then demonstrate it.

I think likewise is true when you are on a train. I`ve often remembered being on a train, shooting passed crossings and their tones alter much in the same way as when you are stationary. Aircraft are another area where I hear this. Not so much in jets as in prop driven and piston planes.

 

[Busaholic]

I happened to catch that at the time of broadcast on Radio 4. I've occasionally thought that if I was hypothetically restricted to one media channel for the rest of my natural, I'd select BBC R4 - for the broadest range of programming, some of the best quality and most intelligent output.

Three radios in my house, all tuned to Radio 4 and at least one of them is on for almost all the hours that Radio 4 broadcasts, every day; and one car radio, ditto, although I admit that on a long car journey I sometimes wish my car wasn't so basic that it has no other aural medium!