Question

If a person lives on the average 100 years in his rest frame, how long does he live in the earth frame if he spends all his life on a spaceship going at 60% of the speed of light.

Answer 1

Explanation:

In the question, it is given:

Proper time is denoted as t, which according to the question is 100 years.

The spaceship has the speed denoted as v = 60100c = 0.60c.

$\Delta \mathrm{t}^{\prime}=\Delta \mathrm{t} 1-\mathrm{v} 2 \mathrm{c} 2=1001-0.602 \mathrm{c} 2 \mathrm{c} 2=125 \mathrm{y}$

So, in the earth frame, the person lives for 125 years if he spends his life on a spaceship moving at the light’s speed at 60%.