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| Momentum and Kinetic Energy |
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| We know that all moving objects possess momentum. Momentum of the body is defined as the product of its mass and the velocity. |
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| Now let us see how kinetic energy of a body is related to its momentum. |
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| Consider a body of mass 'm' moving with a velocity 'v'. Then, momentum of the body is got by |
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| p = mv |
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| Substituting the value of v in equation (1) we get, |
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| 01. Calculate the kinetic energy of a body of mass 5 kg, which is moving with a velocity of 15 m/s. |
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| Solution: |
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| Mass of the body (m) = 5 kg |
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| Velocity of the body (v) = 15 m/s |
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Kinetic energy  |
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| Kinetic energy = 562.5 J |
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| 02. A dog of mass 20 kg is running at a constant speed of 12 m/s. Calculate the kinetic energy of the dog while it is running. |
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| Solution: |
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| Mass of the dog (m) = 20 kg |
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| Velocity (v) = 12 m/s |
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| Kinetic energy of the dog = 1440 J |
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