A car engine is initially rotating at 180 rad/s. It is then turned off and takes 1.20 s to come to a complete stop. What is the angular acceleration of the engine? Assume acceleration is constant.

Question

A car engine is initially rotating at 180 rad/s. It is then turned off and takes 1.20 s to come to a complete stop. What is the angular acceleration of the engine? Assume acceleration is constant.

Answer 1

ω=ωₒ + ε•t,

ω =0,
ε = - ωₒ/t = - 180/1.2 = - 150 rad/s²

Answer 2

To find the angular acceleration of the car engine, we can use the formula:

Angular acceleration (α) = (Final angular velocity (ωf) - Initial angular velocity (ωi)) / Time (t)

Given:
Initial angular velocity (ωi) = 180 rad/s
Final angular velocity (ωf) = 0 rad/s
Time (t) = 1.20 s

We can substitute these values into the formula to find the angular acceleration:

α = (0 - 180) / 1.20

Now, we can calculate:

α = (-180) / 1.20

Simplifying further, we get:

α = -150 rad/s^2

Therefore, the angular acceleration of the car engine is -150 rad/s^2.

Note: The negative sign indicates that the angular acceleration is in the opposite direction of the initial angular velocity, which means the engine is slowing down.