Question

How long would it take a radiowave of frequency, `6 xx 10^(3) sec^(-1)` to travel from Mars to the Earth, a distance of `8 xx 10^(7) km`?

Answer 1

Correct Answer - 4 min 26 sec
All radiation in vacuum travel with the same speed, i.e., `3 xx 10^(8) ms^(-1)`
Distance to be travelled from Mars to the Earth `= 8 xx 10^(7) km = 8 xx 10^(7) xx 10^(3) m (1 km = 10^(3) m)`
`:.` Time taken `= (8 xx 10^(7) xx 10^(3))/(3 xx 10^(8)) = 2.66 xx 10^(2) sec = 4` min 26 sec