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

(Actually, this is not a homework, but a project I'm trying to accomplish

but I have almost forgotten physics...)

There is a disk weighting 100kg with a radius of 0.6 meters. What would be the torque needed to accelerate the disk from 0 rpm to 6 rpm in 10 seconds?

Variables:

m=100 kg

r=0.6 meters

rpmA=0 rpm

rpmB=6 rpm

t=10 seconds

2. Relevant equations

If I'm not wrong:

The mass moment of inertia of a disk with a uniform mass is considered to be:

(m*r^2)/2

where m=mass, r= radius

Converting rpm to radians/sec:

rad/s = rpm * (pi/30)

where pi = 3.14159...

3. The attempt at a solution

So, trying to solve the problem:

moment of inertia of the disk

I = (m*r^2)/2

= (100*0.6^2)/2

= 18

Average angular velocity in radians per second

v = (rpmB-rpmA) * (pi/30)

= 0.628319

Angular acceleration in rad/s^2

a = Angular velocity in radians per sec /t sec

= v/t

= 0.0628319

Torque

T = Angular acceleration * Moment of Inertia

= a*I

= 1.13097

Is this correct?

Is the above result of Torque in Kg-m?

What exactly is the unit of the above inertia result? Is it Kg-m^2 ?

Any help will be appreciated!

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# Homework Help: Required torque to accelerate a disk of a certain mass

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