A car crashes against a wall. The initial velocity at collision is 15m/ sec and the velocity after collision is 2.6 m/sec in the opposite direction. The mass of the car is 1500 kg... force exerted?
- A. 1.76 x 10^5 N
- B. 2.1 x 10^5 N
- C. 2.76 x 10^5 N
- D. None of these
Answer: A. 1.76 x 10^5 N
Explanation: Change in momentum dP = m(v_f - v_i) = 1500(-2.6 - 15) = 1500(-17.6). Force = dP/dt = 1500*17.6 / 0.15 = 10000 * 17.6 = 176000 N = 1.76 * 10^5 N.