A) four times
B) double
C) half
D) unchanged
Correct Answer: A
Solution :
According to the law of conservation of angular momentum \[{{I}_{1}}{{\omega }_{1}}={{I}_{2}}{{\omega }_{2}}\] or \[{{M}_{1}}R_{1}^{2}{{\omega }_{1}}={{M}_{2}}R_{2}^{2}{{\omega }_{2}}\] Given: \[{{M}_{1}}={{M}_{2}},\]\[{{R}_{1}}=2{{R}_{2}}\] \[\therefore \] \[{{M}_{1}}{{(2{{R}_{2}})}^{2}}{{\omega }_{1}}={{M}_{1}}R_{2}^{2}{{\omega }_{2}}\] or \[{{\omega }_{2}}=4{{\omega }_{1}}\] Thus, angular velocity will becomes four time to that of in 1st case.You need to login to perform this action.
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