00:01
Hi there, so for this problem we have a cylinder with a mass of 10 kilograms and we know that the moment of inertia of a cylinder is 1 divided by 2 times its mass times its radius to the square.
00:15
With the radius that is given and that radius is equal to 30 centimeters that will be 0 .3 meters.
00:22
That is rotating about a vertical axis through its center.
00:26
If the angular momentum is increasing, so what we are given is the rate of change of the angular momentum with respect to time that is equal to 25 in units of kilometers times meters squared per second squared, then what is the torque? now, to answer this, let's first define what is the torque.
00:46
The torque usually is defined as the radius, that will be the radius of the point of rotation to the point of application of the force, and the force f.
01:00
And we know that we can write this as just the mass times the acceleration for the force.
01:05
And remember that the angular momentum can be written as just the cross product or in magnitude as the product between the radius times the momentum...