Given, Moment of inertia I=1.6×10−3kg.m2 ,
Initial angular speed ω0=0 ,final angular speed ω=1200×602π=40πrad/s ,time t=15s ,
i). Angular acceleration
α=tω−ω0⟹α=1540π=38πrad/s2 ii).
Unbalanced torque
τ=Iα⟹τ=1.6×10−3×38π=13.40×10−3Nm iii). Let the required angle is θ , thus
ω2=ω02+2αθ⟹θ=2αω2−ω02⟹θ=238π(40π)2=942.47radAlternatively, we can apply
θ=ω0t+21αt2
and eventually we will get the same result.
iv).
By applying work energy theorem for rotational motion we get,
Wrot=21Iω2−21Iω02 Thus we get,
Wrot=21×1.6×10−3(40π)2=12.63J Hence we done.
Comments
Leave a comment