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An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0 . The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.
Is the momentum of the rail car + bowling balls system conserved in this collision ?
  • a)
    Yes, the momentum is completely conserved
  • b)
    Only the momentum component in the vertical direction is conserved
  • c)
    Only the momentum component parallel to the track is conserved
  • d)
    No components are conserved
Correct answer is option 'C'. Can you explain this answer?
Most Upvoted Answer
An isolated rail car of mass M is moving along a straight, frictionles...
Conservation of Momentum

The principle of conservation of momentum states that the total momentum of a system remains constant if no external forces act on it. In other words, the total momentum before a collision is equal to the total momentum after the collision.

The Rail Car and Bowling Balls System

In this scenario, we have a rail car moving at an initial speed v0 along a straight, frictionless track. A crate filled with N bowling balls, each of mass m, is dropped from a bridge into the rail car. The crate splits open and the bowling balls bounce around inside the rail car.

Conservation of Momentum in the Vertical Direction

When the bowling balls are dropped into the rail car, they exert an upward force on the rail car due to the impact. This force causes the rail car to experience an upward acceleration.

Since there is an external force acting on the rail car in the vertical direction, the momentum in the vertical direction is not conserved. The force exerted by the bowling balls on the rail car causes a change in its momentum in the vertical direction.

Conservation of Momentum Parallel to the Track

In the absence of any external forces parallel to the track, the momentum of the rail car and bowling balls system is conserved in the horizontal direction.

The horizontal momentum of the system is given by the mass of the rail car (M) multiplied by its velocity (v) plus the sum of the masses of the bowling balls (N * m) multiplied by their velocity (0, as they are dropped vertically into the rail car).

Initially, the rail car has a momentum of M * v0 in the horizontal direction. After the bowling balls are dropped into the rail car, the system still has a total momentum of M * v0 in the horizontal direction.

Therefore, the momentum component parallel to the track is conserved in this collision.

Conclusion

In conclusion, the momentum of the rail car and bowling balls system is not completely conserved. The momentum component in the vertical direction is not conserved due to the upward force exerted on the rail car by the falling bowling balls. However, the momentum component parallel to the track is conserved as there are no external forces acting on the system in that direction.
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Newton's CradleThe device consists of a row of five metal balls positioned to just barely touch one another suspended from a frame by thin wires. On a small cradles, the balls are hung from the crossbars by light wire, with the balls at the point of an inverted triangle. This ensures that the balls can only swing in one plane, parallel to the crossbars. If the ball could move on any other plane, it would impart less energy to the other balls in the impact or miss them altogether, and the device wouldn't work as well, if at all. All the balls are, ideally, exactly the same size, weight, mass and density. As long as the balls are all the same size and density, they can be as big or as small as you like. The balls must be perfectly aligned at the center to make the cradle work the best.When a ball on one end of the cradle is pulled away from the others and then released, it strikes the next ball in the cradle, which remains motionless. But the last ball on the opposite end of the row is thrown into the air, then swings back to strike the other balls, starting the chain reaction again in reverse. This device illustrates the three main principles of Physics - conservation of energy, conservation of momentum and friction. Everything that moves has momentum equal to its mass multiplied by its velocity. Like energy, momentum is also conserved. Momentum is a vector quantity, when 1st ball hits 2nd ball, it's traveling in a specific direction, let's say east to west. This means that its momentum is also moving east to west. Any change in direction of the motion brings a change in the momentum, which cannot happen without the influence of an outside force. That is why 1st ball doesn't simply bounce off 2nd ball, the momentum carries the energy through all the balls in a westward direction. It is to remember that the law of conservation only works in a closed system, which is free from any external force. The Newton's cradle is not a closed system. When 5th ball swings out away from the rest of the balls, it is affected by the force of gravity, which brings the ball down. But, the horizontal line of balls at rest, functions as a closed system, free from any influence of any force other than gravity. It's here, during the small time between the first ball's impact and the 5th ball swinging out, that momentum is conserved.When the momentum is conserved in Newton’s cradle?

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An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer?
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An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer? for Class 11 2024 is part of Class 11 preparation. The Question and answers have been prepared according to the Class 11 exam syllabus. Information about An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer? covers all topics & solutions for Class 11 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer?.
Solutions for An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 11. Download more important topics, notes, lectures and mock test series for Class 11 Exam by signing up for free.
Here you can find the meaning of An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer?, a detailed solution for An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer? has been provided alongside types of An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice An isolated rail car of mass M is moving along a straight, frictionless track at an initial speed v0. The car is passing under a bridge when a crate filled with N bowling balls, each of mass m, is dropped from the bridge into the bed of the rail car. The crate splits open and the bowling balls bounce around inside the rail car, but none of them fall out.Is the momentum of the rail car + bowling balls system conserved in this collision ?a)Yes, the momentum is completely conservedb)Only the momentum component in the vertical direction is conservedc)Only the momentum component parallel to the track is conservedd)No components are conservedCorrect answer is option 'C'. Can you explain this answer? tests, examples and also practice Class 11 tests.
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