# Theory of special relativity -clocks and objects

## Homework Statement

relative to a stationary observer, how does a moving clock run by comparison? similarly, relative to a stationary observer, how does the size of a moving object compare?

## The Attempt at a Solution

I'm not wholly certain my answers are correct and would love if someone would let me know if they are or are not.

For both parts I'm assuming the non-stationary person and the object are moving at the speed of light. Just because there is no other information given. For the first part of the question I'm guessing that the stationary observer is looking at the clock belonging to the person moving at the speed of light (not that that's possible...) and that time speeds up so that time passes by visibly?

For the second part of the question I would think that if the object is moving at the speed of light, an observer would see it at the same height but the depth of the object would be very small in comparison. Correct?

I don't know... this question is poorly worded considering it lacks certain information so I am unsure if I am interpreting this question correctly.

tiny-tim
Homework Helper
Hi ally1h!
relative to a stationary observer, how does a moving clock run by comparison? similarly, relative to a stationary observer, how does the size of a moving object compare?

For both parts I'm assuming the non-stationary person and the object are moving at the speed of light.

For the second part of the question I would think that if the object is moving at the speed of light …

I don't know... this question is poorly worded considering it lacks certain information so I am unsure if I am interpreting this question correctly.

Whoa!

Nothing goes at the speed of light (well, ok … except light ).

Nul points!

Stop complaining about the question … there's nothing wrong with it … it's just asking about time dilation and Lorentz-Fitzgerald contraction.

(and if a question doesn't give the speed, then call it v )