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.
As the Lorentz transformation suggests there will be time dilation for a moving object with respect to rest frame which is given by 
Where 
, V is velocity of moving object and C is speed of light in vacuum i.e. 
And 
is time in rest frame.
ATQ, 
60 % of C i.e. 
The person will live 
in the spaceship with respect to earth frame.
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