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A man, holding a weight in each hand, stands at the center of a horizontal frictionless rotating turntable. The effect of the weights is to double the rotational inertia of the system. As he is rotating, the man opens his hands and drops the two weights. They fall outside the turntable. Then:

A. his angular velocity doubles
B. his angular velocity remains about the same
C. his angular velocity is halved
D. the direction of his angular momentum vector changes
E. his rotational kinetic energy increases

Respuesta :

Answer:

A. his angular velocity doubles

Explanation:

As we can see that there is no friction force on the platform as well as there is no external torque on the system of rotating platform

so here we can say that angular momentum is conserved in this system

so here we can say that

[tex]L_i = L_f[/tex]

so we know that

[tex]I_1 \omega_1 = I_2\omega_2[/tex]

since the man release the two balls due to which the inertia of the ball is released from the system

so we have

[tex]I_1 = I + I = 2I[/tex]

[tex]I_2 = I[/tex]

now we have

[tex]2I(\omega_1) = I(\omega_2)[/tex]

[tex]\omega_2 = 2\omega_1[/tex]

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