A solid ball of mass 0.5 kg attached to a cord of length 0.8 m rotates in a horizontal circle at a constant speed of 4.0 m/s. Find the centripetal force acting on the ball.

Answer and explanation

Correct answer: C. 10 N

  1. Step 1: Centripetal force formula: F_c = m v² / r. Step 2. Substitute values: F_c = (0.5 × 4.0²) / 0.8 = (0.5 × 16) / 0.8 = 8.0 / 0.8 = 10 N. Answer: 10 N. Why not the others: 8 N is mv²; 12 N and 16 N represent arithmetic errors.

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