- #1

PeachBanana

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## Homework Statement

A grinding wheel is a uniform cylinder with a radius of 10.0 cm and a mass of 0.570 kg.

Calculate its moment of inertia about its center.

*2.85 x 10^-3 kg * m^2*

Calculate the applied torque needed to accelerate it from rest to 1700 rpm in 4.80s if it is known to slow down from 1700 rpm to rest in 57.0s .

## Homework Equations

I = 1/2 Mr^2

ω final - ω initial / t = α

τ = Iα

## The Attempt at a Solution

1700 rpm = 178.02 rad./s

τ = Iα

τ = (2.85 * 10^-3 kg * m^2)(37.0815 rad./s^2) = 0.1056 N*m (Accelerating from rest to 1700 rpm in 4.80 s)

τ = (2.85*10^-3 kg * m^2)(-3.123 rad./s^2) = -0.00890 N*m (Decelerating from 1700 rpm to rest in 57.0s)

I have these two torques and I'm unsure of what to do with them.