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.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Force and Motion
Displacement, velocity and acceleration describe motion, including the horizontal and vertical components of projectile motion. The chapter connects these quantities with Newton's laws, momentum and impulse, then applies conservation of momentum to collisions, distinguishing elastic collisions from inelastic ones.
Practise Force and Motion
1,416 free Force and Motion MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Force and Motion questions
The P.E gained by projectile when it reaches at maximum height is expressed by equation;
Angle between action and reaction forces is:
A body moves in semi-circle of radius 4. What is the displacement of the body?
A body moves from point P(3,4) to Q (5,7). Its displacement vector would be:
A body covers half of the distance with 2ms-1 and other half with 4ms-1then average speed is:
A missile is fired for maximum range with an initial velocity of 20 m/s. If g=10m/s2, the range of the missle is: