A puck on a frictionless air hockey table has a mass of 5.0 g and is attached to a cord passing through a hole in the surface as in the figure. The puck is revolving at a distance 2.0 m from the hole with an angular velocity of 3.0 rad/s. The cord is then pulled from below, shortening the radius to 1.0 m. The new angular velocity (in rad/s) is
A) 4.0
B) 6.0
C) 12
D) 2.0
E) 8.0

Question

A puck on a frictionless air hockey table has a mass of 5.0 g and is attached to a cord passing through a hole in the surface as in the figure. The puck is revolving at a distance 2.0 m from the hole with an angular velocity of 3.0 rad/s. The cord is then pulled from below, shortening the radius to 1.0 m. The new angular velocity (in rad/s) is 
A) 4.0 
B) 6.0 
C) 12 
D) 2.0 
E) 8.0

Quizplus · Accepted Answer

The Answer is C

A Puck on a Frictionless Air Hockey Table Has a Mass