A horizontal ring of radius `r` spins about its axis with an angular velocity `omega` in a uniform vertical magnetic field of magnitude `B`. The emf induced in the ring is

A non-conducting disk of radius R is rotating about its own axis with constant angular velocity omega in a perpendicular uniform magnetic field B as shown in figure. The emf induced between centre and rim of disk is

A horizontal rod of length 'l' rotates about a vertical axis with a uniform angular velocity 'omega' . A uniform magnetic field of induction B exists parallel to the axis of rotation. The potential different between the ends of the rod is

A conducting ring of radius r having charge q is rotating with angular velocity omega about its axes. Find the magnetic field at the centre of the ring.

A conducting ring of radius r having charge q is rotating with angular velocity omega about its axes. Find the magnetic field at the centre of the ring.

A conducting ring of radius r having charge q is rotating with angular velocity omega about its axes. Find the magnetic field at the centre of the ring.

A metallic ring of radius r with a uniform metallic spoke of negligible mass and length r is rotated about its axis with angular velocity omega in a perpendicular uniform magnetic field B as shown in Fig. 3.163. The central end of the spoke is connected to the rim of the wheel through a resistor R as shown. The resistor does not rotate, its one end is always at the center of the ring and the other end is always in as shown is needed to maintain constant angular velocity of the wheel. F is equal to (the ring and the spoke has zero resistance)