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Sum1
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Homework Statement
(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
Homework 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...
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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