The motion of copper plate is damped, when it is allowed to oscillate between the two poles of a magnet. What is the cause of this damping?

The displacement current is produced across the gap between the two plates of a capacitor, when the charge on the capacitor

For a given potential difference, does a capacitor store more or less charge with a dielectric than it does without a dielectric constant (K) is inserted between the two plates of capacitor. What is the new of charge stored in the capacitor?

Figure shows a metal rod PQ resting on the smooth rails AB and positioned between the poles of a permanent magnet. The rails, the rod, and the magnetic field are in three mutual perpendicular directions. A galvanometer G connects the rails through a switch K. Length of the rod =15 cm, B = 0.50 T, resistance of the closed loop containing the rod = 9.0 mOmega Assume the field to be uniform. What is the retarding force on the rod when K is closed? :

Figure shows a metal rod PQ resting on the smooth rails AB and positioned between the poles of a permanent magnet. The rails, the rod, and the magnetic field are in three mutual perpendicular directions. A galvanometer G connects the rails through a switch K. Length of the rod =15 cm, B = 0.50 T, resistance of the closed loop containing the rod = 9.0 mOmega Assume the field to be uniform. Is there an excess charge built up at the ends of the rods when K is open? What if K is closed? :

Figure shows a metal rod PQ resting on the smooth rails AB and positioned between the poles of a permanent magnet. The rails, the rod, and the magnetic field are in three mutual perpendicular directions. A galvanometer G connects the rails through a switch K. Length of the rod =15 cm, B = 0.50 T, resistance of the closed loop containing the rod = 9.0 mOmega Assume the field to be uniform. What is the induced emf in the moving rod if the magnetic field is parallel to the rails instead of being perpendicular? :

Two bar magnets having same geometry with magnetic moments M and 2M, are firstly placed in such a way what their similar poles are same side then its time period of oscillation is T_1 . Now the polarity of one of the magnet is reversed then time period of oscillation will be

Two identical magnetic with a length 10 cm and weight 50 g of each are arranged freely with their like poles facing in a inverted vertical glass tube. The upper magnet hangs in the air above the lower one so that the distance between the nearest pole of the magnet is 3mm. Pole strength of the poles of each magnet will be

A thin rectangular magnet suspended freely has a period of oscillation T in a uniform magnetic field . Now it is broken in two equal parts perpendicular to magnetic axis and one place is allowed to oscillate in the same field . If its period of oscillation is T' , then ration (T)/(T') is

A small retangular coil ABCD contains 140 turns of wire. The sides AB and BC of the coil are of length 4.5 and 2.8 cm respectively, as shown in the figure The coil is held between the poles of a large magnet so that the coil can rotate about an axis thorugh its centre. The magnet produces a uniform magnetic field of flux density B between its poles. When the current in the coil is 170 mA, the maximum torque produced in the coil is 2.1 xx 10^-3 N m . Use your answer to show that the magnetic flux density B between the poles of the magnet is 70 mT.