A brake is applied to a rotating disk, initially moving counterclockwise, causing it to slow down with a constant angular acceleration of magnitude 5.00 rad/s2. Immediately after the brake is applied, the disk rotates through 50.4 rad during a 4.00 s time interval. What is the angular speed (in rad/s) of the disk at the end of this time interval

The angular speed at the end of this time interval (t=4 s) is 12.6 rad/s.

Explanation:

When applied the brake, the velocity will be decreasing at a constant rate of 5 rad/s

We know that in the first 4 seconds, the displacement of the disk is 50.4 rad.

Now that we know the initial angular speed, we can calculate the angular speed at t=4s

The angular speed at the end of this time interval (t=4 s) is 12.6 rad/s.

current flows in a wire