Two discs have moments of inertia I₁ and I₂ rotating... | Rotational Motion

JEE-MAIN 2021

27-08-2021 S2

Question

Two discs have moments of intertia $l_1$ and $l_2$ about their respective axes perpendicular to the plane and passing through the centre. They are rotating with angular speeds, $\omega_1$ and $\omega_2$ respectively and are brought into contact face to face with their axes of rotation coaxial. The loss in kinetic energy of the system in the process is given by :

Select the correct option:

$\frac{I_1 I_2}{\left(I_1+I_2\right)}\left(\omega_1-\omega_2\right)^2$

$\frac{\left(I_1-I_2\right)^2 \omega_1 \omega_2}{2\left(I_1+I_2\right)}$

$\frac{I_1 I_2}{2\left(I_1+I_2\right)}\left(\omega_1-\omega_2\right)^2$

$\frac{\left(\omega_1-\omega_2\right)^2}{2\left(I_1+I_2\right)}$

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

Solution