A particle of mass moves in a horizontal circle of radius at a constant speed of on the end of a light string. Find the tension.

Answer and explanation

Correct answer: B.

  1. Step 1: The tension supplies the centripetal force: .
  2. Step 2: N.
Answer
.
Why not the others: is what you get if you forget to square the speed. is what you get if you invert the formula. is what you get if you multiply by the radius.

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