Car B overtakes another car A at a relative speed of 40 m s - 1 . How fast will the image of car B appear to move in the mirror of focal length 10 cm fitted in car A , when the car B is 1 . 9 m away from the car A ?

Step-by-step solution

Object distance, u = − 1.9   m = 190   cm Focal length, f = 10   cm Magnification, m = f f − u = 10 10 − ( − 190 ) Therefore, m = 10 200 = 1 20 Image velocity, V I = − m 2 V 0 = − 1 20 2 × 40 Hence, V I = − 0.1   m   s - 1 Magnitude of velocity = 0 . 1   m   s - 1