A DISTANT SPACE PROBE IS PROGRAMMED TO EMIT A RADIO SIGNAL TOWARD EARTH AT REGULAR TIME INTERVALS. ONE SUCH PULSE ARRIVES ON EARTH 2.92S AFTER IT IS EMITTED FROM THE PROBE. WHAT IS THE APPROXIMATE DISTANCE FROM THE EARTH TO THE PROBE?

Question

A DISTANT SPACE PROBE IS PROGRAMMED TO EMIT A RADIO SIGNAL TOWARD EARTH AT REGULAR TIME INTERVALS. ONE SUCH PULSE ARRIVES ON EARTH 2.92S AFTER IT IS EMITTED FROM THE PROBE. WHAT IS THE APPROXIMATE DISTANCE FROM THE EARTH TO THE PROBE?
A) 7.4 X 10^8M
B) 8.76 X 10^8M
C) 6.94 X 10^8M
D) 3.50 X 10^8M
E) 4.12 X10^8M

drwls · Answer

Multiply the travel time by the speed of light and see which os the choices is closest. You should have memorized the speed of light by now.