Question

4. Let’s say you wanted to impress your friends with your new “time travelling” DeLorean. You challenge them saying that you will meet them at your favourite reunion spot exactly 50 years later, and you would only age a year. You go and buy the best clock you can find, an atomic clock made of Caesium atoms. Now you sit in the DeLorean and it asks you to enter the speed as a percentage of the speed of light. Before you do so, you calculate what the speed should exactly be.

Show your calculation.

[Disclaimer: Enter with good accuracy. The lives of your friends are at stake.]

Answer 1

According to relativity of time

Where,
Time spend by your friends
Time spend by you
Speed of time machine
Speed of light

Therefore, you need to enter 99.98% of the speed of the light to meet them exactly after yours 1 year and your friends 50 years.