Question

An electric fan is turned off, and its angular velocity decreases uniformly from 460rev/min to 160rev/min in a time interval of length 3.60s .

Find the number of revolutions made by the motor in the time interval of length 3.60s .

Answer 1

w^2f=w^2i+2αθ
find alpha fromwf=wi+αt
our final omega will be
23/3 rev.s /sec

our initial omega will be
8/3 rev.s /sec

and
t= 3.6 sec
put values and you will get the answer.