Mars is roughly 60million km from earth. How long does it take for a radio signal originating from earth to reach Mars? (Hint: use the speed of light)

It will take 200 s for the radio signal to reach Mars.

The speed of light, ##c## is ##3.00xx10^8## ##"m/s"## to three . All electromagnetic radiation, such as radio waves, travel at the speed of light. Since ##c## is in m/s, convert the distance to Mars from kilometers to meters by multiplying kilometers by 1000.

##60,000,000cancel"km"xx(1000"m")/(1cancel"km")=60,000,000,000 "m"=6.00xx10^10"m"##

Now divide the distance in meters by the speed of light in m/s.

##(6.00xx10^10cancel"m")/(3.00xx10^8cancel"m"/"s")="200 s"##