Physics
Mechanics
Easy

Question

A ball is attached to a string that is attached to a thick pole. When the ball is hit, the string warps around the pole and the ball spirals inwards sliding on the frictionless surface. Neglecting air resistance, what happens as the ball swings around the pole?

  1. The mechanical energy and angular momentum are conserved
  2. The angular momentum of the ball is conserved at the mechanical energy of the ball increases
  3. The angular momentum of the ball is conserved and the mechanical energy of the ball decreases
  4. The mechanical energy of the ball is conserved and angular momentum of the ball decreases

The correct answer is: The mechanical energy of the ball is conserved and angular momentum of the ball decreases


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