TSR Physics Society

x

I've just come up with a brilliant analogy of length contraction using a slinky



What happens when you drop a slinky? The top of it falls while the bottom seems to levitate in the air, until the top comes to meet it. The reason for this is that information cannot travel faster than the speed of light.

Imagine a rocket, one light year long. The engine at the back causes the rocket to move, but not all of it starts to move at the same time.

Let's say that the rocket travels at 100 miles per hour. The back of the rocket will start to move at 100 miles per hour (assuming it accelerates instantaneously from 0). The 'wave' of movement will move up the rocket until (information travelling at the speed of light) a year later the top of the rocket will begin to move at 100 miles per hour.

Since the bottom of the rocket has been travelling for longer than the top, it has travelled a further distance. The rocket is therefore shorter.

For the slinky, the information travels at the same speed as the slinky itself, equivalent to the rocket travelling at the speed of light. So if the rocket were to travel at the speed of light, it would be slinkified and have zero length!





What do you think?


Posted from TSR Mobile

I've just come up with a brilliant analogy of length contraction using a slinky



What happens when you drop a slinky? The top of it falls while the bottom seems to levitate in the air, until the top comes to meet it. The reason for this is that information cannot travel faster than the speed of light.

Imagine a rocket, one light year long. The engine at the back causes the rocket to move, but not all of it starts to move at the same time.

Let's say that the rocket travels at 100 miles per hour. The back of the rocket will start to move at 100 miles per hour (assuming it accelerates instantaneously from 0). The 'wave' of movement will move up the rocket until (information travelling at the speed of light) a year later the top of the rocket will begin to move at 100 miles per hour.

Since the bottom of the rocket has been travelling for longer than the top, it has travelled a further distance. The rocket is therefore shorter.

For the slinky, the information travels at the same speed as the slinky itself, equivalent to the rocket travelling at the speed of light. So if the rocket were to travel at the speed of light, it would be slinkified and have zero length!





What do you think?


Posted from TSR Mobile

x

That is horrible.

Before I am capable of giving an answer to that, I would love to know what a slinky is. The spiral-like spring by any chance?

Yes


Posted from TSR Mobile

Kyx is back in the game! I thought we'd lost you forever

It was only a 7 day ban. Felt like forever 😂😂


Posted from TSR Mobile

You on a final warning kiddo?

This is the new thread for the TSR Physics Society. Listed below are the current members. Feel free to use this thread to discuss physics, or just chat to other physicists.

To join the Physics Society, click on this link http://www.thestudentroom.co.uk/group.php?groupid=248

Founder & President
Hoofbeat

Leader
jpowell

Full Members
2776
aiman
cerebrum_core
ChemistBoy
Edders
hajira
henryt
K'uin K'ra
lgs98jonee
material breach
Mik1w
mizfissy815
MRLX69
neb_revlis
Princess Ana
RDoh
RichE
rpotter
sarz777
Scottus_Mus
sonja
Sparkling_Jules
The_Kangaroo
toipot2
Widowmaker
hira89
AlphaNumeric
F1 fanatic
.S.O.S.


Honorary Members
...GiNuWiNe...
®eAl ©uTe Eye$
AhmadMujtaba
cdm391
darkenergy
DazYaSSS
distortedgav
Elite Cookie
eurasianfeline
fabbo
Fly By
hihihihi
James.R
jinsisi
KiranV
LS
mathemagician
mubinchoudhury
Ol 92650
oxymoron
sayed_samed
Scottus Mus
seth
shushimeng
sunjuice
Swing
tiara123
Willywonker
Wiwarin mir
Z!D4N
mysteryman

Thanks

Can i join the society too please