Exam-style question
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What happens to the rotational kinetic energy of a spinning object if its angular velocity is doubled while its moment of inertia remains constant?.
- A.It remains the same.
- B.It doubles.
- C.It quadruples.
- D.It halves.
Model answer
What a good answer should say
- It quadruples.
Explanation
Why this works
The rotational kinetic energy is proportional to the square of the angular velocity (Ek = 0.5 x I x ω²). If ω is doubled, the energy increases by a factor of 2² = 4, thus it quadruples.
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