Magnets are used in cranes for lifting and moving scrap metals.

Magnets are not used in

Assertion : Magnetic field interacts with a moving charge and not with a stationary charge. Reason : A moving charge produces a magnetic field.

A: The magnetic field always accelerates a moving charge if the moving charge cuts the field lines. R: When a moving charge cuts the magnetic field lines, the magnetic force on the charge is always non zero.

A: The magnetic field lines also represent the lines of force on a moving charged particle at every point. R: Force on a moving charge acts parallel to the magnetic field.

A spring balance and a physical balance are kept in a lift. In these balance equal masses are placed. If now the lift starts moving upward with constant acceleration, then.

A spring balance and a physical balance are kept in a lift. In these balance equal masses are placed. If now the lift starts moving upward with constant acceleration, then.

It is established that an electric current through a metallic conductor produces a magnetic field around it. Is there a similar magnetic field produced around a thin beam of moving (i) alpha particles, (ii) neutrons? Justify your answer.

Discuss how apparent weight of a person in a lift changes when it is (a) moving up with acceleration (b) moving down with acceleration less than acceleration due to gravity (c) moving with uniform velocity (d) when it is stationary.

A: When a bar magnet is dropped into a vertical long hollow metallic tube, the magnet ultimately moves with zera acceleration. R: The magnet falling into metallic tube causes the eddy currents in the metal tube, so the motion of the magnet is damped.