Example of theory of relativity | Learn Physics

 Example of theory of relativity

Example: A rod stationary relative to the earth is found to be 40 m long by an observer on the earth with what velocity must it move parallel to its length so that its apparent length relative to the observer is reduced to ten metres.

Solution:

Here, l₀ =40 m; l=10 m

V=?

L=l₀√(1-v²/c²); 10 = 40  √(1-v²/c²)

1/16 =1-( v²/c²)

=2.88 × 10⁸ m/s