A car of mass 1000 kg moving with 25 ms-1 collide straight with stationary track of mass 1500kg, and start moving together. Find the velocity of track.
Correct answer: C. 10 ms-1
- A. 15 ms-1
- B. 25 ms-1
- C. 10 ms-1
- D. 6 ms-1
Explanation
Option C is correct.In this case, the collision is inelastic, which means that some kinetic energy is lost. The total momentum of the system before and after the collision must be the same. The momentum of the system before the collision is: p = mv = (1000 kg)(25 m/s) = 25000 kg m/s where: m is the mass of the car v is the velocity of the car The momentum of the system after the collision is: p = mv = (1000 kg + 1500 kg)(v) where v is the velocity of the car and the track after the collision. Setting these two equations equal to each other, we get: (1000 kg)(25 m/s) = (2500 kg)(v) Solving for v, we get: v = 10 m/s Therefore, the velocity of the car and the track after the collision is 10 m/s in the same direction as the initial velocity of the car.
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