Electromagnetic...

A conducting ring is placed around the core of an electromagnet as shown in fig. When key K is pressed, the ring

The north and south poles of two identical magnets approach a coil, containing a condenser, with equal speeds from opposite sides. Then

A highly conducting ring of radius R is perpendicular to and concentric with the axis of a long solenoid as shown in fig. The ring has a narrow gap of width din its circumference. The solenoid has cross-sectional area A and a uniform internal field of magnitude B₀. Now beginning at t = 0, the solenoid current is steadily increased, so that the field magnitude at any time t is given by B(t) = B₀ + αt, where α >0. Assuming that no charge can flow across the gap, the end of ring which has excess of positive charge and the magnitude of induced e.m.f. in the ring are respectively

Plane figures made of thin wires of resistance R = 50 milli ohm/metre are located in a uniform magnetic field perpendicular into the plane of the figures and which decrease at the rate dB/dt = 0.1 m T/s. The current in the inner and outer boundary are inner radius a = 10 cm and outer radius b = 20 cm

A rectangular loop with a sliding connector of length l = 1.0 m is situated in a uniform magnetic field B = 2T perpendicular to the plane of loop. Resistance of connector is r = 2 Ω. Two resistors of 6 Ω and 3 Ω are connected as shown in figure. The external force required to keep the connector moving with a constant velocity v = 2m/s is

A wire cd of length land mass m is sliding without friction on conducting rails ax and by as shown. The vertical rails are connected to each other with a resistance R between a and b. A uniform magnetic field B is applied perpendicular to the plane abcd such that cd moves with a constant velocity of

What is the mutual inductance of a two-loop system as shown with centre separation l

The figure shows three circuits with identical batteries inductors, and resistors, Rank the circuits, in the decreasing order, according to the current through the batter (i) just after the switch is closed and (ii) a longtime later

The network shown in the figure is part of a complete circuit. If at a certain instant the current i is 5 A and isdecreasing at the rate of 10³ A/s, then V_A– V_B is