Question

Time Dilation Ranking Task
Five identical quintuplets leave earth when they reach the age of 21, in the year 2121. Each quintuplet goes on a spaceship journey that takes T years, as measured by a clock in each spaceship. During the journey they travel at a constant speed v, as measured on earth, except during the relatively short acceleration phases of their journey.

Part A
Rank these quintuplets on the basis of the year on earth when they return from their journey.
Rank from largest to smallest. To rank items as equivalent, overlap them.

A: T=20years, v=0.4c
B: T= 5years, v=0.2c
C: T=10years, v=0.8c
D: T=10years, v=0.4c
E: T=20years, v=0.8c

Part B
Rank these quintuplets on the basis of their age when they return from their journey.
Rank from largest to smallest. To rank items as equivalent, overlap them.

A: T=20years, v=0.4c
B: T= 5years, v=0.2c
C: T=10years, v=0.8c
D: T=10years, v=0.4c
E: T=20years, v=0.8c

Answer 1

PART A: 20 yrs ,0.8 c then 20yrs, 0.4c then 10yrs, 0.8c then 10 yrs, 0.4c then 5yrs, 0.2c

PART B: 20yrs=20yrs, 10yrs=10yrs, 5yrs

Answer 2

For question B the amount of years you are in space is how many years you will have aged when you return so naturally: 20=20, 10=10, 5

Answer 3

Using on the time dilation formula we can rank the quintuplets. if T' is the time measured by Earth andT is the time measured on space ship, thein Here, v is the speed of the jouney by the earth andc is the speed of the light Part A A: T- 20 years, v 0.4c 20 years (0.4c) - 21.82 years B T-5 years, v-0.2c years 5.10 years C:7-10 years, v-0.8c 10 years (0.8c)2 16.67 years

D:7-10 years, v-04 c 10 years (0.4c) 10.91 years E: T-20 years, v-0.8c T" years 0.8c -33.33 years Hence, the rank from largest to sm allest is E>A>C>D>B PartB: A1l the five quintuplets have same age when they leave the earth. Hence, the order from largest to smallest on the basis of their age is al so same as the part A. E>A>C>D>B