A car engine is initially rotating at 250 rad/s. It is then turned off and takes 4.80 s to come to a complete stop. What is the angular acceleration of the engine

Explanation:

Given

--- initial angular velocity

-- Initial time

Because the engine completely stops, we have the following:

 --- final angular velocity

--- final time

Required:

Determine the angular acceleration ()

The angular is calculated as thus:

i.e. the ratio of change in angular velocity to change in time

Substitute in the required values, the expression becomes:

-- approximated

Hence, the engine's angular acceleration is 52.1rad/s^2