Momentum and Newton's Laws of Motion

Momentum and Newton's Laws of Motion problem 16

A small ring with a mass of can slide frictionlessly along a wire which is twisted into a semicircular loop with radius as shown in the figure below. The semicircular loop is rotated around an axis at an angular velocity .

Figure 1: Rotating semicircular loop with ring

  • Draw the external forces on the ring when the ring is at the height of with respect to the lowest position, and name the forces.

  • Find the relationship between the angular velocity and the height .

  • At what angular velocity is the ring at the height of ?

  • What is the resultant force acting on the ring?

  • What force does the semicircular loop exert on the ring?

  • Explain whether it is possible for the ring to fall off the rotating loop!


material editor: Joanah Frank