What is the outward force acting on a mass of 10 kg when rotating at one end an inelastic string 10m long at speed of 1m/s ?
Correct answer: A. 1N
- A. 1N
- B. 10N
- C. 2N
- D. 100N
Explanation
The required centripetal force, often described as an apparent outward centrifugal force in the rotating frame, has magnitude F = mv2/r. Substituting m = 10 kg, v = 1 m s^-1 and r = 10 m gives F = (10 kg × 1 m2 s^-2)/(10 m) = 1 N. Students may choose 10 N by using mv instead of mv2/r or by confusing force with mass times speed.
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