Question

The rear view mirror of a car is a plane mirror. A driver is reversing his car at a speed of 2m/s. The driver sees in his rear view mirror the image of truck parked behind his car. The speed at which the image of the truck appears to approach the driver will
i) 1m/s
ii) 2m/s
iii) 4m/s
iv) 8m/s
Give the reason also.

Answer 1

The speed at which the image of the truck appears to approach the driver will be Option iii)4m/s.

The car is traveling at an initial speed of 2m/s which states the car is approaching with a speed of 2 m per second. Also, the mirror is a plane mirror so the speed at which the car is reversing is the same as that of the truck is approaching. So the speed at which the image of the truck will appear to approach the driver will be

⇒(2+2)m/s

⇒4m/s.