Question

A police van moving on a highway with a speed of 30 km/h fires a bullet at a thief's car speeding away in the same direction with a speed of 192 km/h. If the muzzle speed of the bullet is 150 m is, with what speed does the bullet hit the thief's car?

Options

• 475/3 m/s

• 160/3 m/s

• 150 m/s

• 105 m/s

Answer 1

105 m/s

Explanation:

Given V_p = 30 km/h, V_T = 192 km/h, V_BP = 150 m/s = 540 km/h

∴ Speed of buttle w.r.t police V_an, V_BP = V_B - V_P = 540

∴ V_B = 540 + 30 = 570 km/h.

And speed of bullet w.r.t. theif's car = V_BP = V_B - V_T or V_BT = 570 - 192 = 378 km/h

`= (378 xx 5)/15` = 105 m/s