What happens to the size of a moving object? If a rocket is coming toward you, h

Question

What happens to the size of a moving object? If a rocket is coming toward you, how are its x, y, and z dimensions affected from your perspective?

In a nut shell, this is how I would explain these two questions (please correct me if wrong or if further detail is needed)

The size of a moving object (where v is getting closer to c) will appear shorter in the direction in which it is moving. (so if the object is moving in the x direction, it will appear shorter in the x direction). If a rocket is coming towards me in the x dimension, the x dimension will appear to be shorter, and y & z will remain the same.

Explanation / Answer

This can be eplained by Length Contraction.

Length contraction is the phenomenon of a decrease in length of an object as measured by an observer which is traveling at any non-zero velocity relative to the object.This contraction  is usually only noticeable at a substantial fraction of the speed of light. Length contraction is only in the direction parallel to the direction in which the observed body is travelling. This effect is negligible at everyday speeds, and can be ignored for all regular purposes.As the magnitude of the velocity approaches the speed of light, the effect becomes dominant, as can be seen from the formula:

L = Lo*sqrt[1 - (v/c)^2]

where

L0 is the proper length (the length of the object in its rest frame),

L is the length observed by an observer in relative motion with respect to the object,

v is the relative velocity between the observer and the moving object,

c is the speed of light,

and sqrt[1 - (v/c)^2] =  Lorentz factor

so if the object is moving in the x direction, it will appear shorter in the x direction. If a rocket is coming towards you in the x dimension, the x dimension will appear to be shorter, and y & z will remain the same.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.