Taking the speed of the radio signal as 3×108 m/s, calculate the time taken for a signal to reach a GPS receiver from a GPS satellite at a position 21 000 km distant from the receiver. Assume that the speed of the signal is unchanged over the whole path length. Express your answer in milliseconds

1 answer

d = V*t = 21*10^6 m.
t = 21*10^6/3*10^8 = 7*10^-2 s. = 70 ms.