A light disc made of aluminum (a nonmagnetic material ) is kept horizontally and is free to rotate about its axis as shown in the figure. A strong magnet is held vertically at point above the disc away from its at

A circular disc is rotating about its own axis, the direction of its angular momentum is

A horizontal disc is rotating about a vertical axis passing through its centre. If an insect moves from centre to rim then the angular momentum of the system

A horizontal disc is rotating about a vertical axis passing through its centre. If an insect moves from centre to rim then the angular momentum of the system

A centrifuge has a horizontal cylinder rotating about a vetical axis as shown in the figure. Water inside it has density rho . (a) Consider a point A. Inside the liquid, at a distance r from the rotation axis. Liquid pressurea t his point is P. Write the value of (dP)/(dr) when the cylinder, with all its liquid. rotates uniformly at an angular speed omega . (ii) Consider a small disc shaped foreign material inside the centrifuge at point A. The area of circular disc is DeltaS and its thickness is Deltar . It disc is in position so that its circular face is vertical. Find the radial acceleration of the disc with respect to the cylinder when angular speed of rotation is

A disc of a mass M and radius R can rotate freely in vertical plane about a horizontal axis at O . Distant r from the centre of disc as shown in the figure. The disc is released from rest in the shown position. The angular acceleration of disc when OC rotates by an angles of 37^(@) is

A non-conducting disc having unifrom positive charge Q , is rotating about its axis with unifrom angular velocity omega .The magnetic field at the centre of the disc is.

The general motion of a rigid body can be considered to be a combination of (i) a motion of its centre of mass about an axis, and (ii) its motion about an instantaneous exis passing through the centre of mass. These axes need not be stationary. Consider, for example, a thin uniform disc welded (rigidly fixed) horizontally at its rim to a massless, stick as shown in the figure. When the disc-stick system is rotated about the origin on a horizontal frictionless plane with angular speed omega the motion at any instant can be taken as a combination of (i) a rotation of the disc through an instantaneous vertical axis passing through its centre of mass (as is seen from the changed orientation of points P and Q). Both these motions have the same angular speed omega in this case Now consider two similar system as shown in the figure: Case (a) the disc with its face vertical and parallel to x-z plane, Case (b) the disc with its face making an angle of 45^@ with x-y plane and its horizontal diameter parallel to x-axis. In both the cases, the disc is welded at point P, and the systems are rotated with constant angular speed omega about the z-axis. Which of the following statements regarding the angular speed about the instantaneous axis (passing through the centre of mass) is correct?

A uniform semicircular disc of mass 'm' and radius 'R' is shown in the figure. Find out its moment of inertia about. (a) axis 'AB' ( shown in the figure 0 which passes through geometrical centre and lies in the plane of the disc (b) axis 'CD' which passes through its centre of mass and it is perpendicular to the plane of the disc.

When a circular disc of radius 0.5 m is rotating about its own axis, then the direction of its angular momentum is

A brass disc is rotating about its axis. If temperature of disc is increased then its