- #1

nickb145

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## Homework Statement

An electric trimmer blade has rotational inertia 1.55×10−4kg⋅m2 .

What torque is needed to accelerate this blade from rest to 605rpm in 1.05s ?

How much work was done to accelerate the blade?

## Homework Equations

Torque=Ixα

rpm=>Rad/s

α=Δω/Δy

## The Attempt at a Solution

Ok so i converted RPM to Rev/s first. which is 63 rad/s now substituting it in for α and multiply it by the Inertia will get me the torque of 9.35x10^-3N-m

Angular Velocity i think is 66.15rad/s. Because ω=α*T

For the work, it is just the change in kinetic energy right? K=(.5)(I)ω^2 i keep getting a wrong answer