A particle is moved in a circle with a constant angular velocity. Its angular momentum is L. If the radius of the circle is halved, keeping the angular velocity the same, the angular momentum of the particle will become:
Correct answer: A. L/4
- A. L/4
- B. L/2
- C. L
- D. 2L
Explanation
When the radius of the circle is halved while keeping the angular velocity constant, the angular momentum decreases by a factor of 4. This is because angular momentum is directly proportional to the radius squared. Therefore, the correct answer is L/4. Options B, C, and D are incorrect because they do not consider the relationship between angular momentum, radius, and angular velocity.L = Iω∴ L₂/L₁ = I₂/I₁ [∵ ω = const.]or L₂/L₁ = m(r/2)² / mr² = 1/4⇒ L₂ = L₁/4
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