The rigid body shown in the fig. (a) has a mass of 10 kg. It rotates with a uniform angular velocity ω. A balancing mass of 20 kg is attached as shown in fig.(b). The percentage increase in mass moment of inertia as a result of this addition is
50%
Moment of inertia of first
=mk2=10×(0.2)2
=0.4kg.m2
Moment of inertia of second
=m1k21+m2k22
=10×(0.2)2+20×(0.1)2
=0.6kg.m2
∴Increases in mass moment of inertia
=0.6−0.40.4×100=50%