A wheel on a game show is given an initial angular speed of 1.22 rad/s. It comes

Question

A wheel on a game show is given an initial angular speed of 1.22 rad/s. It comes to rest after rotating through 3/4 of a turn. Find the average torque exerted on the wheel given that it is a disk of radius 0.71 m and mass 6.4 kg. A 15.0-kg child is sitting on a playground teeter-totter, 1.50 m from the pivot. What force, applied 0.300 m on the other side of the pivot, is needed to make the child lift off the ground? The drive chain in a bicycle is applying a torque of 0.850 Nm to the wheel of the bicycle. Treat the wheel as a hoop with a mass of 0.750 kg and a radius of 33.0 cm. What is the angular acceleration of the wheel?

Explanation / Answer

1. Applying wf^2 - wi^2 = 2 alpha theta

0^2 - (1.22^2) = 2(alpha) ((3/4) (2pi) )

alpha = 0.158 rad/s^2

and torque = I alpha

I = m R^2 /2 = (6.4)(0.71^2) / 2 = 1.613 kg m^2

torque = 0.255 N m

2. (15 x 9.81) ( 1.50) = (0.3 F)

F = 735.75 N

3. I = 0.750 x 0.33^2 = 0.0817 kg m^2

torque = I alpha

alpha = 10.41 rad/s^2

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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