Department of Pre-University Education, KarnatakaPUC Karnataka Science Class 11

# A Diver Having a Moment of Inertia of 6⋅0 Kg-m2 About an Axis Thorough Its Centre of Mass Rotates at an Angular Speed of 2 Rad/S About this Axis. - Physics

Sum

A diver having a moment of inertia of 6⋅0 kg-m2 about an axis thorough its centre of mass rotates at an angular speed of 2 rad/s about this axis. If he folds his hands and feet to decrease the moment of inertia to 5⋅0 kg-m2, what will be the new angular speed?

#### Solution

Initial moment of inertia of diver, I1 = 6 kg-m2

Initial angular velocity of diver, ω1 = 2 rad/s

Final moment of inertia of diver, I2 = 5 kg-m2

Let ω2 be the final angular velocity of the diver.

We have

External torque = 0

∴ I1ω1 = I2ω2

$\Rightarrow \omega_2 = \frac{6 \times 2}{5} = 2.4 \text{ rad/s}$

Is there an error in this question or solution?

#### APPEARS IN

HC Verma Class 11, 12 Concepts of Physics 1
Chapter 10 Rotational Mechanics
Q 52 | Page 198