Question

Suppose at a concert a singers voice is radio broadcast all the way around the world before reaching the radio you hold to your ear . How long does this take . __ seconds

I don't understand thisss ! Help me !

Answer 1

Radius of earth = about 6.4*10^6 meters
circumference = 2 pi r
time = distance/speed = 2 pi r/343

Answer 2

agrrrh, used sound in air not light
2 pi r / (3*10^8)