Car A (mass = 1000 kg) moves to the right along a level, straight road at a speed of 6.0 m/s. It collides directly with car B (mass = 200 kg) in a completely inelastic collision. What is the speed of the car immediately after the collision?
A) 5.0 m/s
B) 6.0 m/s
C) 4.0 m/s
D) 3.0 m/s
E) zero

Question

Quizplus · Accepted Answer

In a completely inelastic collision, the two objects stick together after the collision. The conservation of momentum principle applies, which states that the total momentum before the collision equals the total momentum after the collision. The initial momentum is the sum of the momenta of the two cars: (1000 kg * 6.0 m/s) + (200 kg * 0 m/s) = 6000 kg*m/s (since car B is stationary, its initial momentum is 0). The combined mass after the collision is 1000 kg + 200 kg = 1200 kg. To find the final speed (v), use the formula for momentum (p = mv), so 6000 kg*m/s = 1200 kg * v. Solving for v gives v = 6000 kg*m/s / 1200 kg = 5.0 m/s.

Car a (Mass = 1000 Kg) Moves to the Right