Question

A car is sitting still. It accelerates to a constant speed then it decelerates again to zero speed. While the car is accelerating how do the directions of the angular acceleration and angular velocity of one of the wheels compare

Answer 1

Answer:

in the acceleration process the quantity α and w must increase

the deceleration process the alpha quantity must constant  a direction opposite to the angular velocity

Explanation:

Acceleration and angular velocity are related to linear

           v = w xr

            a = αx r

The bold letters indicate vectors and the cross is a vector product, therefore if

we can see that the relationship between linear and angular variables is direct

therefore in the acceleration process the quantity α and w must increase as well as their linear counterparts

in the deceleration process the alpha quantity must constant as the linear acceleration and must have a direction opposite to the angular velocity