A helicopter has a large main rotor that rotates in a horizontal plane and provides lift. There is also a small rotor on the tail that rotates in a vertical plane.What is the purpose of the tail rotor ?

There is an insulator rod of length L and of negligible mass with two small balls of mass m and electric charge Q attached to its ends. The rod can rotate in the horizontal plane around a vertical axis crossing it at a L//4 distance from one of its ends. What is the time period of the SHM as mentioned in previous question?

A uniform rod of mass m and length l rotates in a horizontal plane with an angular velocity omega about a vertical axis passing through one end. The tension in the rod at a distance x from the axis is

A uniform metal rod is rotated in horizontal plane about a vertical axis passing through its end at uniform rate. The tension in the rod is

A uniform circular disc of radius R oscillates in a vertical plane about a horizontal axis. Find the distance of the axis of rotation from the centre of which the period is minimum. What is the value of this period?

The electric current in a straight wire is constant and wire is kept along east-west line at a point in a horizontal plane. A point P is located to the north side of wire at some distance. What is the direction of magnetic induction at point P. If the wire is rotated in horizontal plane hy an angle 30^(@) then what will be the direction at point P.

A person stands in contact against the inner wall of a rotor of radius r. The coefficient of friction between the wall and the clothing is mu and the rotor is rotating about vertical axis. The minimum angular speed of the rotor so that the person does not slip downward is

A weightless rigid rod with a load at the end is hinged at point A to the wall so that it can rotate in all directions (Fig). The rod is kept in the horizontal position by a vertical inextensible thread of length 1, fixed at its midpoint. The load receives a momentum in the direction perpendicular to the plane of the figure. Determine the period T of small oscillations of the system.