A car is fitted with a convex side-view mirror of focal length 20 cm. A second car 2.8 m behind the first car is overtaking the first car at a relative speed of 15 m/s. The speed of the image of the second car as seen in the mirror of the first one is

- (1/10) m/s
- (1/15) m/s
- 10 m/s
- 15 m/s

**Answer**

Mirror formula:

(1/v) + (1/-280) = 1/20

(1/v) = (1/20) + (1/280)

v = 280/15

v_{1} = -(v/u)^{2} v_{om}

v_{1} = -(280/15X280)^{2} . 15

v_{1} = -15/(15x15)

v_{1} = -1/15 m/s

**The correct option is B.**