Time dilation on Helios satellite traveling to Jupiter

[wowolala]

An astronaut traveling on the Helios satellite (the fastest human made craft) goes on a trip to Jupiter and back in 75 days as measured by an observer on the Earth. If the average speed of the satellite is a quarter of a million km/h with respect to the Earth , what is the time difference ( in seconds) between the time recorded by the clock on the Earth and the one on board the satellite?



honestly, i am really confused on this part , can somebody help me?

thx so much

 

[tiny-tim]

Hi wowolala!

Find the speed, v (as a multiple of c).

Then the clock on the satellite will go slow by … ?

Then multiply by the time (75 days converted into seconds).