If a light body and a heavy body have equal momentum, then

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Q: 60 (NDA-II/2009)
If a light body and a heavy body have equal momentum, then

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,26,26,26,12,7,7

keywords: 

{'equal momentum': [0, 0, 1, 0], 'greater kinetic energy': [0, 0, 1, 0], 'lesser kinetic energy': [0, 0, 1, 0], 'momentum': [0, 1, 0, 3], 'kinetic energy': [0, 0, 4, 7], 'heavier body': [0, 0, 1, 0], 'lighter body': [0, 0, 1, 0], 'light body': [0, 0, 1, 0], 'heavy body': [0, 0, 1, 0], 'bodies': [0, 0, 3, 10]}

The correct answer is option 1: the lighter body has greater kinetic energy than the heavier body.

To understand why this is the case, we need to remember that kinetic energy depends on both mass and velocity. The formula for kinetic energy is KE = 1/2 * mass * velocity^2.

Given that the momentum of the light body and heavy body is equal, we can write their momentum as P = mass * velocity.

Since the momentum is the same, we can equate the two equations as follows:

mass of the light body * velocity of the light body = mass of the heavy body * velocity of the heavy body

Dividing both sides by the mass of the light body, we get:

velocity of the light body = (mass of the heavy body / mass of the light body) * velocity of the heavy body

This equation tells us that the velocity of the light body is greater than the velocity of the heavy body, since the mass of the heavy body is greater than the mass of the light body.

Now, plugging this velocity into the equation for kinetic energy, we can see that the kinetic energy of the light body will be greater than the kinetic energy of the heavy body.

Therefore, option 1 is correct.