Consider a spot of flourescent paint on a tyre sidewall

Consider a spot of flourescent paint on a tyre sidewall

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Discussion

singlecoil

Original Poster:

34,666 posts

261 months

Sunday 15th March 2009
quotequote all
The flourescent paint is just to make it easier to see.

Anyway, if the car was to be photographed from the side, in motion, at night, with a camera with its shutter open, what shape would the path of the spot make on the exposed film (or digital equivalent)?

Trommel

20,152 posts

274 months

Sunday 15th March 2009
quotequote all

King Herald

23,501 posts

231 months

Sunday 15th March 2009
quotequote all
singlecoil said:
The flourescent paint is just to make it easier to see.

Anyway, if the car was to be photographed from the side, in motion, at night, with a camera with its shutter open, what shape would the path of the spot make on the exposed film (or digital equivalent)?
A long wavy curtate cycloid line.

Not circles, unless you were to accidentally 'smoke the hides'..... biggrin

Edited by King Herald on Sunday 15th March 17:59

Cabinet Enforcer

502 posts

241 months

Sunday 15th March 2009
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The shape is called a cycloid, looks a bit like a series of semi-circles, but they aren't.

Bushmaster

27,480 posts

294 months

Sunday 15th March 2009
quotequote all
Same shape you would get putting the paint spot on the arse of a Kangaroo. A lot of jumps.

mrmr96

13,736 posts

219 months

Sunday 15th March 2009
quotequote all
This:

HTH

singlecoil

Original Poster:

34,666 posts

261 months

Sunday 15th March 2009
quotequote all
Bushmaster said:
Same shape you would get putting the paint spot on the arse of a Kangaroo. A lot of jumps.
I'm unconvinced by that response, unless the motion of a kangaroo's arse is circular?

Bushmaster

27,480 posts

294 months

Sunday 15th March 2009
quotequote all
singlecoil said:
Bushmaster said:
Same shape you would get putting the paint spot on the arse of a Kangaroo. A lot of jumps.
I'm unconvinced by that response, unless the motion of a kangaroo's arse is circular?
Yeah? See the cycloid shape above then.




singlecoil

Original Poster:

34,666 posts

261 months

Sunday 15th March 2009
quotequote all
mrmr96 said:
This:

HTH
Interesting. But would there be a crossing point? Would not a crossing point indicate that the spot had been in the same place twice? (assming the camera was not moving)

edited to add about the camera being stationary

Edited by singlecoil on Sunday 15th March 13:20

Bushmaster

27,480 posts

294 months

Sunday 15th March 2009
quotequote all
singlecoil said:
mrmr96 said:
This:

HTH
Interesting. But would there be a crossing point? Would not a crossing point indicate that the spot had been in the same place twice?
STEP AWAY FROM THE GCSE PHYSICS BOOK. IT WILL FRY YOUR BRAIN.

ian in lancs

3,842 posts

213 months

Sunday 15th March 2009
quotequote all
mrmr96 said:
This:

HTH
Clear proof of a life wasted on Spirograph!!!

dibbers006

14,492 posts

233 months

Sunday 15th March 2009
quotequote all
Off you go...



wink

jeff m

4,066 posts

273 months

Sunday 15th March 2009
quotequote all
Sceptics go to the chapter on loci.

(used in engineering for all oscilating parts to make sure they don't collide with other bits)

Simpo Two

89,131 posts

280 months

Sunday 15th March 2009
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Epicyclic curve if spot is at circumference.

singlecoil

Original Poster:

34,666 posts

261 months

Sunday 15th March 2009
quotequote all
Simpo Two said:
Epicyclic curve if spot is at circumference.
Well, I did say a spot on the sidewall, so not on the circumference.

TheEnd

15,370 posts

203 months

Sunday 15th March 2009
quotequote all
dibbers006 said:
Off you go...



wink
WARNING!! I HAVE BAD TASTE!