HELP WITH PART D!!!!!! Learning Goal: To use linear and angular momentum to solv

Question

HELP WITH PART D!!!!!!

Learning Goal:

To use linear and angular momentum to solve simple problems.

As shown, a thin metal disk is rolling without slipping along a flat horizontal surface, its velocity in the x direction is v1=34.5 ft/s, and its angular velocity is ?1=23.0 rad/s. The disk is 3.00 ft in diameter, has a thickness of 0.60 in, and has a density of 12 slug/ft3. Positive angular velocity is in the counterclockwise direction.

Part C - Change in linear momentum

The disk from Part A is now moving in the opposite direction with a velocity of v2=21.0 ft/s and an angular velocity of ?2=14.0 rad/s in the direction shown in (Figure 2) . What is the change in the disk

Explanation / Answer

R = radius of disk = d/2 = 1.5 ft

Vcm1 = intial velocity of centre of mass = RW2 = 1.5*14   = 21 ft/s

Vcm2 = final velocity of centre of mass = R*W3 = 1.5 w3 ft/s

Li = intial angular mometum about instantanuos axis of rotaion ( about contact point on ground)

    = I*W2 + MR*Vcm1

   =4.768*14 + 4.239 *1.5*21

= 200.28

L2 = final angular momentum

     = Iw3 + MR*Vcm2

   = 4.768*w3 + 4.239*1.5*1.5w3

= 14.3 w3

Now ::: L2 -L1 =-19.2

             14.3 w3 -200.28 = -19.2

                W3 =12.66 K rad/s

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.