Question

A person travels on a spaceship moving at a speed of 5c/13. (a) Find the time interval calculated by him between the consecutive birthday celebrations of his friend on the earth. (b) Find the time interval calculated by the friend on the earth between the consecutive birthday celebrations of the traveller.

Answer 1

Explanation:

In the question, it is given:  

Speed of spaceship, u = 5c13

(a) Proper time, t = 1 yr

The person calculates the time interval as t’, which is equal to $t 1-u 2 / c 2$

$=1 \mathrm{yr} 1-25 \mathrm{c} 2169 \mathrm{c} 2=13 / 12 \mathrm{years}$

So, the time interval on Earth estimated by that person in spaceship between the successive birthday parties of his friend is 13/12 years.

(b) The time interval calculated by the friend on Earth considers the same speed, which is 13/12 years.