00:01
Determine the angular acceleration of the spool.
00:05
Okay, so we can draw our free body diagram.
00:11
For our spool, we have our normal force.
00:17
Here's our different radii, our weight force, and we also have a force p applied.
00:25
Now we can apply equilibrium along the x axis.
00:28
We have p plus our friction force equal to mass time's acceleration.
00:32
So plucking in, we have 600 plus.
00:35
Plus f is equal to 100a.
00:38
And along the y -axis, we get normal force is equal to m times g, or 981 newtons.
00:47
We can also apply our moment equilibrium about our point, about this point.
00:53
Let's see, the moment of equilibrium is equal to our moment of inertia times alpha.
00:59
But this is negative f, r2, plus p times r1, is equal to i alpha.
01:06
And so we get negative f, r2, plus pr1 is equal to m k squared alpha...