MEDIUM
JEE Main
IMPORTANT
Earn 100

The radius of gyration of a uniform disc about a line perpendicular to the disc equals its radius. The distance of the line from the centre is given as ra. Find the value of a

50% studentsanswered this correctly

Important Questions on Rotational Mechanics

HARD
JEE Main
IMPORTANT
The moment of inertia of a uniform square plate of mass m and edge a about one of its diagonals is given as ma2β. Find the value of β.
HARD
JEE Main
IMPORTANT
The surface density massarea of a circular disc of radius a depends on the distance from the centre as ρr=A+Br. The moment of inertia about the line perpendicular to the plane of the disc through its centre is given by 2πAa4α+Ba5β. Find the value of α+β.
MEDIUM
JEE Main
IMPORTANT
A particle of mass m is projected with a speed u at an angle θ with the horizontal. The torque of the weight of the particle is muxsinθcosθ, which is perpendicular to the plane of motion. The value of x is:
MEDIUM
JEE Main
IMPORTANT
A simple pendulum of length l is pulled aside to make an angle θ with the vertical. The magnitude of the torque of the weight w of the bob about the point of suspension is xsinθ. The torque is zero when the bob is at the lowest point. The value of x is:
MEDIUM
JEE Main
IMPORTANT

When a force of 6.0 N is exerted at 30° to a wrench at a distance of 8 cm from the nut, it is just able to loosen the nut. What force F would be sufficient to loosen it if it acts perpendicularly to the wrench at 16 cm from the nut?

 Question Image

MEDIUM
JEE Main
IMPORTANT

Calculate the total torque acts on the body shown about the point O.

Question Image

HARD
JEE Main
IMPORTANT
A cubical block of mass m and edge a slides down a rough inclined plane of inclination θ with uniform speed. The torque of the normal force acts on the block about its centre is y mgasinθ. The value of y is:
HARD
JEE Main
IMPORTANT
A rod of mass m and length L lying horizontally is free to rotate about a vertical axis through its centre. The horizontal force of constant magnitude F acts on the rod at a distance of L4 from the centre. The force is always perpendicular to the rod. The angle rotated by the rod during the time t after the motion starts is given as αFt2mL. Find the value of α.