The increase in rotational kinetic energy.
Answer to Problem 1OQ
Option (b) the rotational kinetic energy increases by factor
Explanation of Solution
Write the expression for
Here,
Write the expression for rotational kinetic energy of an object.
Here,
Conclusion:
Consider an ice skater is behaves like isolated system.
For conservative angular momentum when moment of inertia decreases by factor
Substitute
From the above expression clearly shows the rotational kinetic energy becomes double.
Thus, the rotational kinetic energy increases by factor
When M.O.I decreases by four times than the rotational kinetic energy increases by factor
When moment of inertia decreases than the rotational kinetic energy can’t be constant so option (c) is incorrect.
When moment of inertia decreases than the rotational kinetic energy can’t decreases so option (d) is incorrect.
When moment of inertia decreases than the rotational kinetic energy can’t decreases so option (e) is incorrect.
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Chapter 11 Solutions
Physics for Scientists and Engineers with Modern Physics, Technology Update
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