List of top Physics Questions on Rotational motion asked in COMEDK UGET

A bullet fired into a door gets embedded exactly at its center, causing the door to rotate about its vertical hinge axis practically without friction with an angular velocity of $625\text{ rad s}^{-1}$. The door is $0\text{ m}$ wide and weighs $12\text{ kg}$. If the mass of the bullet is $10\text{ g}$, find the speed with which it was fired. (Hint: The moment of inertia of the door about the vertical axis at one end is $I = \frac{ML^2}{3}$)}

A singer, during his performance, stands on the edge of a circular turntable and begins to walk along its edge with a speed of $5\text{ m s}^{-1}$ relative to the ground. The turntable is mounted on a frictionless vertical axle. Its radius $R = 3\text{ m}$ and its moment of inertia about the axle is $150\text{ kg m}^2$. It is initially at rest. If the mass of the singer is $75\text{ kg}$, the time taken by the man to complete one full revolution relative to the ground is:

Applying a constant torque the speed of a flywheel is increased from \(1800\) rpm to \(2400\) rpm in \(10\) seconds. The number of revolutions made by the flywheel during this time is:

A bullet of momentum \( p \) is fired into a door and gets embedded exactly at the center of the door. The door is \( 1.0 \, \text{m} \) wide and weighs \( 12 \, \text{kg} \). It is hinged at one end and rotates about a vertical axis practically without friction. The angular speed of the door just after the bullet embeds into it is: