Constant Torque Find magnitude of friction force

[sarahjt1]

Homework Statement

A grinding wheel of radius 0.330m rotating on a frictionless axle is brought to rest by applying a constant friction force tangential to its rim. The constant torque produced by this force is 72.1 N*m. Find the magnitude of the friction force.

I'm honestly lost at even starting this problem but below are some equations that I THINK are relevant but I don't really know.

Homework Equations

torque=I alpha, where I = 1/2MR^2.

This is where I get confused because we are not given a mass....

The Attempt at a Solution

 

[sarahjt1]

Nevermind... silly me. Much simpler than I thought.

 

[kerimek]

To find the magnitude of the friction force, we need to use the equation for torque, which is equal to the product of the force and the distance from the axis of rotation. In this case, the distance from the axis of rotation is the radius of the grinding wheel, 0.330m. So we can write the equation as:

Torque = Force * Distance

We are given that the torque produced by the friction force is 72.1 N*m. So we can rewrite the equation as:

72.1 N*m = Force * 0.330m

Solving for the force, we get:

Force = 72.1 N*m / 0.330m = 218.48 N

Therefore, the magnitude of the friction force is 218.48 N.