(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A constant torque of 25.5 N · m is applied to a grindstone whose moment of inertia is

0.117 kg · m2.

Using energy principles, and neglecting friction, find the angular speed after the grind-

stone has made 14.6 rev.

Answer in units of rad/s

2. Relevant equations

1 rad = 1/2π rev (π = pi)

T=Iα (α = alpha = angular acceleration)(T=torque)

α=Δω/t

3. The attempt at a solution

All I've got it that 14.6 rev = 91.7345...rad.

... I think those are the only relevant equations since we don't know the radius or the mass OR the initial velocity of the grindstone. (Do we assume it was at rest? Does it even matter?) I must be wrong though as I am stumped on how to solve this. Thank you to anyone able and kind enough to help!

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# Homework Help: Finding angular speed given T and I

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