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2 years ago

6

1. If a model train car with a momentum of 12 kg•m/s collides with a 2 kg model train car that is not moving, what is the total

momentum of both cars after the collision?

1 answer:

wariber [46]2 years ago

7 0

Answer:

$P_{f} = 12 \ kg.m/s$

Explanation:

Given data:

Momentum of moving model train, $P_{1} = 12 \ kg.m/s$

Mass of the stationary model train, $m = 2 \ kg$

Initial speed of the stationary model train, $v = 0$

Assume there is no external force is acting on the given train system.

In this case, the total linear momentum of the trains would be conserved.

Let the final linear momentum of the trains be $P_{f}.$

Thus,

$P_{i} = P_{f}$

$P_{1} + P_{2} = P_{f}$

$P_{1} + mv = P_{f}$

$12 + 2 \times 0 = P_{f}$

$\Rightarrow \ P_{f} = 12 \ kg.m/s.$

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2 years ago

A hammer slides down a roof that makes a 30.0°angle with the horizontal. What are the magnitudes of the components of the hammer

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Explanation:

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3 years ago

Consider a rigid body that rotates but whose center of mass is at rest. True or false: the rotational kinetic energy of the enti

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Answer:

True

Explanation:

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2 years ago

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Answer:

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