The driver of a car moving with uniform speed of 40ms-1 observes a truck approaching from the opposite direction with a speed of 20ms-1. Calculate the speed...

The driver of a car moving with uniform speed of 40ms^-1 observes a truck approaching from the opposite direction with a speed of 20ms^-1. Calculate the speed of the car relative to that of the truck

Answer Details

The relative speed of the car with respect to the truck is the difference between their speeds. Since the truck is moving in the opposite direction, its speed is taken as negative. Thus: Relative speed = speed of car - speed of truck = 40ms^-1 - (-20ms^-1) = 40ms^-1 + 20ms^-1 = 60ms^-1 Therefore, the speed of the car relative to that of the truck is 60ms^-1.