Question

How long (in s) does it take for a radio signal from the earth to reach an astronaut on the moon? The distance from the earth to the moon is 2.4 x 105 mi.

Answer 1

t=s/c
where t= time taken (we need to find)
s=2.4*105 miles (convert to meters)
c=speed of light(3*10^8)

Answer 2

How did you know to use speed of light?

Answer 3

radio signals are Electromagnetic waves, Even light is Electromagnetic waves.
You will get your answer.....Sure....
@mtimko

Answer 4

If it was useful, don't forget to medal.... and fan....