Question

Three identical triplets leave earth when they reach the age of 21,in the year 2121. Each triplet goes on a spaceship journey thattakes T years, as measured by a clock in each spaceship. During thejourney they travel at a constant speed v , as measured on earth,except during the relatively short acceleration phases of theirjourney. (Triplets occur when three babies are borntogether.)

Part A)
The triplets return to Earth in different years according to peoplewho stay on Earth. Rank the triplets on the basis of the year onearth when they return from their journey. That is, work out theyear when each triplet returns, and then rank the tripletsaccording to the largest return year to the smallest returnyear.

A- T= 20 years, v=0.4
B- T= 10 years, v=0.8
C- T= 10 years, v=0.4

NOTE: The product of the time measured on the spaceship and thefactor sqrt(1-v^2/c^2) does not equal the time elapsed onearth.

Part B)
Calculate the age of each triplet when they return from theirjourney. Rank the triplets on the basis of their return age.

A- T= 10 years, v=0.4
B- T= 20 years, v=0.4
C- T= 10 years, v=0.8

thanks heaps......