vikas askiitian expert
Last Activity: 13 Years ago
@ = at - bt3 ...............1
d@/dt = W = a-3bt2 ...............2
dW/dt = alfa = -6bt ............3
body comes to rest when angular velocity becomes 0
a - 3bt2 = 0
t = (a/3b)1/2
mean value of angular velocity = (@t - @0)/t
@0=0
@t= a(a/3b)1/2 - b(a/3b)3/2
= a(a/3b)1/2[1-1/3]
=(2a/3)(a/3b)1/2
mean value of angular velocity = 2a/3(a/3b)1/2/t = 2a/3 = 4rad/sec
now mean value of angular accleration = change in angular velocity/t = (Wt-W0)/t
at t=0 W=a , at T=t Wt = 0
mean value = a/t = (3ab)1/2
=(36)1/2=6rad/sec2