Velma passes Mort at a speed of 0.75c. At this speed, the "time dilation factor" is 1.5. In other words, Mort observes a 1- second tick of Velma's clock to take 1.5 seconds. Suppose that they are born at the same time, and that Mort observes himself to live 30 years. As Mort dies, how old will he observe Velma to be?
A) 10 years
B) 20 years
C) 30 years
D) 40 years
E) 45 years

Question

Quizplus · Accepted Answer

Due to time dilation, Mort observes Velma's clock to run slower by a factor of 1.5. Therefore, when Mort lives 30 years, he observes Velma to age 30 / 1.5 = 20 years.

Velma Passes Mort at a Speed of 0