The kinetic energy of a body rotating at 300 revolutions per minute is 62.8 J. Its angular momentum (in `kg m^(2)s^(-2)`) is approximatelyA. 1B. 2C. 4D. 8

The kinetic energy of a body rotating at 300 revolutions per minute is

1.	The kinetic energy of a body rotating at 300 revolutions per minute is 62.8 J. Its angular momentum (in `kg m^(2)s^(-2)`) is approximatelyA. 1B. 2C. 4D. 8
Answer» Correct Answer - C 300 rpm = 5 rps `omega = 2pi (5) = 10 pi rad s^(-1)` Kinetic energy `=(1)/(2)I omega^(2)=(1)/(2)L omega` `therefore " " L = (2(KE))/(omega)=(2(62.8))/(10pi)` `= 4 kgm^(2)//s^(1)`.

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The kinetic energy of a body rotating at 300 revolutions per minute is 62.8 J. Its angular momentum (in `kg m^(2)s^(-2)`) is approximatelyA. 1B. 2C. 4D. 8

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