A hollow tube is carrying an electric current along its length distributed uniformly over its surface. The magnetic field

A rubber balloon is given a charge Q distributed uniformly over its surface. Then

A rubber balloon is given a charge Q distributed uniformly over its surface. Then

A long cylinder of wire of radius 'a' carries a current i distributed uniformly over its cross section. If the magnetic fields at distances rlta and Rgta from the axis have equal magnitude, then

A long cylinder of wire of radius 'a' carries a current i distributed uniformly over its cross section. If the magnetic fields at distances rlta and Rgta from the axis have equal magnitude, then

Statement 1: A direct uniformly distributed current flows through a solid long metallic cylinder along its length. It produces magnetic field only outside the cylinder. Statement 2: A thin long cylindrical tube carrying uniformly distributed current along its length does not produce a magnetic field inside it. Moreover, a solid cylinder can be supposed to be made up of many thin cylinderical tubes.

Current flows through a straight cylindrical conductor of radius r. The current is distributed uniformly over its cross-section. The magnetic field at a distanace x from the axis of the conductor has magnitude B:

A long, straight wire of radius R carries a current distributed uniformly over its cross section. The magnitude of the magnetic field is