Question

If we have a stick one light year long and if we displace one of its end will the other end move immediately.

Explain your answer in at least 100 words.

Regards,
TheBlaze

:)

Answer 1

Hi friend,

This is a logical and imaginary question.

But anyhow thanks for asking!!!!


By creating an infinitely rigid stick, every atom would have an infinite electrical potential with every other atom in the stick. This, regardless of what the stick was made of, would in turn make it infinitely massive. The bond between the atoms would be so strong that, once you had made this infinitely rigid stick, every atom would have enough energy to break free of the confines of the stick, and it would probably instantly disintegrate.

It turns out that the rigidity of the stick prevents one of the physical laws from being broken, namely that nothing can travel faster than light . Even if our stick didn’t disintegrate, and our infinitely strong man pushed the infinitely rigid stick, the latter would likely fall apart as the compression wave of the push passed down it. Alternatively, if we didn’t have an infinitely strong man to hand, the stick would be immovable...


This is just a assumed theory.But it is not possible!!!

Hope this helps you..


Thanks.
@saka82411

Answer 2

Well to give you a direct answer, a " BIG NO"  The other end wont move immediately . but sure it will move thats after 74400 years

If that would happened, wouldn't it be amazing, We would be able to beat the speed of light. But thats impossible. :(


Now for the reason.!!!

In practical life situation when you move a stick ,it moves immediately from the other end.This is because the stick we use is very small, and we see immediate reaction.

But what if stick is very very very long??? , just like you mentioned 1 light year long. (which is practically impossible) but still can be considered as a thought experiment.


To answer this we need to know

how the other end of the stick moves in the first place?

When you give a force from one end of the stick the particles present at the end, exerts a force on its nearby particles and comes back to its normal position, this particle now exerts the force on its nearby particles and comes back to rest, this pattern continuous,till the force is exerted on the endmost particle.
And then the other end moves,but as mention when the length of stick is so small this effect is nullified and we see it as an immediate action.

This work just like how the sound wave is propagated, compression rarefaction then again compression rarefaction, in the longitudinal wave format,instead of air particles here we have particles with which the stick is made.

Thats the reason i mention the maximum speed with which the stick could move is with the speed of sound.

So by moving the stick from one end ,the compression rarefaction moves, and this compression rarefaction to reach the other end of the stick it would take around 74400 yrs  :O 

No comparison to speed of light, anything having mass can never travel faster than light. !!!