Answer:
α=1.013rev/min^2
Step-by-step explanation:
Wo=initial angular speed=158rev/min
t=time=2.6h=156min
Wf=final angular speed=0rev /min , this happens because in the end the wheel stops
this is a circular motion with uniform acceleration therefore we can use the following equation
α=angular aceleration=(Wf-Wo)/t
α=(0-158)/156=1.013rev/min^2