Electromagnetic...

A rectangular conductor PQRS in which the conductor PQ is free to move is kept in a magnetic field B ,which is perpendicular to the PQRS which lies in a single plane. If the conductor PQ has a length l,moves with a speed v, then induced emf is

A 500-loop circular wire coil with radius 4.00 cm is placed between the poles of a large electromagnet. The magnetic field is uniform and makes an angle of  60^∘  with the plane of the coil; it decreases at 0.200 T/s . Magnitude of induced emf is

Use Lenz ’s law to determine the direction of induced current in the situations described by the Figure (a) A wire of irregular shape turning into a circular shape; (b) A circular loop being deformed into a narrow straight wire. The directions for (a) and (b) respectively are

An air-cored solenoid with length 30 cm, area of cross-section 25  cm²  and number of turns 500, carries a current of 2.5 A. The current is suddenly switched off in a brief time of  10⁻³ s. Average back emf induced across the ends of the open switch in the circuit is

If two coils of inductances  L₁  and  L₂  are linked such that their mutual inductance is M, then

Eddy Currents are

Polarity of the capacitor in the situation described by the adjacent figure is

A 1.0 m long metallic rod is rotated with an angular frequency of 400 rad  s⁻¹  about an axis normal to the rod passing through its one end. The other end of the rod is in contact with a circular metallic ring. A constant and uniform magnetic field of 0.5 T parallel to the axis exists everywhere. Emf developed between the centre and the ring is

On a cylindrical rod two coils are wound one above the other. What is the coefficient of mutual inductance if the inductance of each coil os 0.1H?

Two ends of a horizontal conducting rod of length l are joined to a voltmeter. The whole arrangement moves with a horizontal velocity v, the direction of motion being perpendicular to the rod. Vertical component of the earth 's magnetic field is B. The voltmeter reads