Asanding disk with rotational inertia 6.5 x 10-3 kg·m2 is attached to an electric drill whose motor delivers a torque of magnitude 21 n·m about the central axis of the disk. about that axis and with torque applied for 54 ms, what is the magnitude of the (a) angular momentum and (b) angular velocity of the disk?

The angular momentum and angular velocity are 1.134 kg.m²/s and 174.5 rad/s.

Explanation:

Given that,

Moment of inertia

Torque = 21 N.m

Time dt = 54 ms

(a). We need to calculate the angular momentum

Using formula of torque

Where, dL = angular momentum

t = time

= torque

Put the value into the formula

(b). We need to calculate the angular velocity of the disk

Using formula of angular velocity

Hence, The angular momentum and angular velocity are 1.134 kg.m²/s and 174.5 rad/s.

if the forces acting on an object are unbalanced, the object will accelerate in the direction of the net force on the object.

explanation:

this is best explained by having an understanding of newton's second law, which states that f=ma. you see, when the forces are unbalanced, net force (sum of all forces) is not zero. therefore making it necessary for the object to have an acceleration in the direction of the net force.