Part A Determine the ratio of the instantaneous speeds of the two balls v A/ v B
ID: 1476433 • Letter: P
Question
Part A
Determine the ratio of the instantaneous speeds of the two balls vA/vB at the moment shown.
* A freely rotating object will rotate about its center of mass.
The answer is NOT infinity, 2, or 3
Problem 12.12 The system shown in (Figure 1) consists of two balls A and B connected by a thin rod of negligible mass. Ball A has two times the inertia of ball B and the distance between the two balls is l. The system has a translational velocity of v in the x direction and is spinning counterclockwise at an angular speed of Figure 1of 1Explanation / Answer
The smaller ball will have vb = v-(wl/2) and larger ball will have va=v+(wl/2). This will be the instantaneous velocity.
Since w = v/l, vb = v- ((v/l)*l/2) = v/2.
va= v+((v/l)*l/2) = 3v/2.
Thus, ratio is = (3v/2) / (v/2) = 3.
Note: Here if w=2v/l, the problem is not solved.