When a body moves in a circle of radius r with linear speed V its centripetal force is_______________?
Correct answer: C. mV2/r
- A. mV/r2
- B. mV/r
- C. mV2/r
- D. mV2/r2
Explanation
For circular motion, the required centripetal acceleration is v²/r, so Newton's second law gives F = m(v²/r) = mV²/r. The force increases with the square of speed and decreases as radius increases. The likely mistake is choosing mV/r, which omits the second factor of speed.
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