A rigid body rotates about a fixed axis with variable angular velocity equal to(a bt) at t where a and b are constants. The angle through which it rotates before it comes to rest is
ω=a−bt=0t=a/bθ=∫ωdt=∫ab0(a−bt)dt=[at−bt22]a/b0=a.ab−b2[a2b2]=a22b
B is the correct option