Answer:
The angular acceleration of a point on the wheel is
and it is decelerating.
Step-by-step explanation:
It is given that,
Radius of the wheel, r = 0.1 m
Initial angular velocity of the wheel,
![\omega_i=35\ rev/s=219.91\ rad/s](https://img.qammunity.org/2021/formulas/physics/college/nqoprrpnifuv8gorpa3726bn0x1yc18rte.png)
Final angular velocity of the wheel,
![\omega_f=15\ rev/s=94.24\ rad/s](https://img.qammunity.org/2021/formulas/physics/college/1pkevws6jlsjk9w6v3tmukocqxj0d9zi7k.png)
Time, t = 3 s
We need to find the angular acceleration of a point on the wheel. It is given by the rate of change of angular velocity divided by time taken. It is given by :
![\alpha =(\omega_f-\omega_i)/(t)](https://img.qammunity.org/2021/formulas/physics/college/84krnebqzwph82ab8xkukn4r3fpktjrg5s.png)
![\alpha =((94.24-219.91)\ rad/s)/(3\ s)](https://img.qammunity.org/2021/formulas/physics/college/4l9i0t1nsy1ns05kibf6uyfxbevqmc83o7.png)
![\alpha =-41.89\ rad/s^2](https://img.qammunity.org/2021/formulas/physics/college/u87n5wwyee1w2oi92fb356tbc9pty3cs8f.png)
So, the angular acceleration of a point on the wheel is
and it is decelerating. Hence, this is the required solution.