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Question
A car is accelerated on a levelled road and attains a speed of 4 times its initial speed. In this process, the kinetic energy of the car :
Options
does not change
becomes 4 times that of initial kinetic energy
becomes 8 times that of initial kinetic energy
becomes 16 times that of initial kinetic energy
Solution
Kinetic energy of a body is directly proportional to the square of the velocity. So, the kinetic energy will become 16 times its initial value if the velocity is increased 4 times.
Therefore, the answer is,
(d) becomes 16 times that of initial kinetic energy.
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