A man stands holding a weight in each hand and with his arms outstretched on a frictionless platform which is rotating at a speed of 1 revolution per sec. In ths position the total rotational intertia of the man, the weights and the platform is `6kgm^(2)`. If by drawing in his arms, the man decreases the rotational inertia of the system by `2kg m^(2)`, calcualte the resulting speed of the platform and the increase in kinetic energy. How do you account for the increase of kinetic energy?A. 2 rpsB. 4 rpsC. 3 rpsD. 6 rps

A man stands holding a weight in each hand and with his arms outstretc

1.	A man stands holding a weight in each hand and with his arms outstretched on a frictionless platform which is rotating at a speed of 1 revolution per sec. In ths position the total rotational intertia of the man, the weights and the platform is `6kgm^(2)`. If by drawing in his arms, the man decreases the rotational inertia of the system by `2kg m^(2)`, calcualte the resulting speed of the platform and the increase in kinetic energy. How do you account for the increase of kinetic energy?A. 2 rpsB. 4 rpsC. 3 rpsD. 6 rps
Answer» Correct Answer - C `I_(1)omega_(1)=I_(2)omega_(2)`

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