Question

a point source s is placed at a distance of 10 cm from centre of the mirror of width 20 cm suspended vertically.An insect moves with velocity 10 cm/s along a line parallel to the mirror Find the maximum time duration in which insect can see the image of source.

Answer 1

Mass of the ball, m = 150 g = 0.15 kg

Initial speed of the ball, u = -12 m/s

Final speed of the bal after being hit, v = 20 m/s

Impulse = change in momentum = final momentum initial momentum

= Impulse = 0.15 × 20 0.15 × (-12) = 4.8 Ns