Home
Class 12
PHYSICS
A solid flywheel of 20 kg mass and 120 m...

A solid flywheel of 20 kg mass and 120 mm radius revolves at 600 r.p.m. With what force must a brake lining be pressed against it for the flywheel to stop in 3 s, if the coefficient of friction is 0.1?

Text Solution

Verified by Experts

The correct Answer is:
`2.5 xx10^2N`
The work of the force of friction is responsible for the loss of the entire kinetic energy of the flywheel. We have
`DeltaK = (Iomega^2)/2=(mr^2omega^2)/4, W_r=Tl=muNv_(av)t=(muNomegart)/2`
Hence
`N = (mromega)/(2mut)=(pi m rn)/(mut)`
Try to solve this problem with the aid of the fundamental equation of rotational dynamics of a rigid body.
Promotional Banner

Similar Questions

Explore conceptually related problems

A solid flywheel of 20 kg mass and 120 mm radius revolves at 600 "revmin"^(-1) . With what force must a brake lining be pressed against it for the flywheel to stop in 3s, if the coefficient of friction is 0.1 ?

A solid flywheel of mass M and radius r revolves with an angular velocity m. With what force must a brake lining be pressed against it for the flywheel to stop in t seconds, if mu is the coefficient of friction?

A flywheel of mass 10 kg and radius 10 cm is revolving at a speed of 240 r.p.m. Its kinetic energy is

If a flywheel of mass m kg and radius r m is revolving at n rps, then the kinetic energy of rotation will be

A flywheel of mass 25 kg has a radius of 0.2 m. What force should be applied tangentially to the rim of the flywheel so that it acquires an angular acceleration of 2 "rad s"^(-2) ?

A scooter weighs 120 kg f. Brakes are applied so that wheels stop rolling and start skidding. Find the force of friction if the coefficient of friction is 0.4 .

Given in figure are two blocks A and B of weight 20N and 100N, respectively. These are being pressed against a wall by a force F as shown. If the coefficient of friction between the blocks is 0.1 and between block B and the wall is 0.15, the frictional force applied by the wall on block B is:

A rectangular block of mass 6 kg is to be held against a rough vertical wall by appplying a force perpendicular to the wall. What is the minimum force to be applied, if the coefficient of friction is 0.42?

A flywheel of mass 25 kg has a radius of 0.2 m. It is making 240 r.p.m. what is the torque necessary to bring it to rest in 20 s ? If the torque is due to a force applied tangentially on the rim of the flywheel, what is the magnitude of the force ?