If a long copper rod carries a direct current, the magnetic field associated with the current will be

A long hollow copper pipe carries a current. Then, the magneic field product is

A long solenoid has 200 turns per cm and carries a current i. The magnetic field at its centre is 6.28xx10^(-2)Wb//m^(2) . Another long solenoid has 100 turns per cm and it carries a current i/3. The value of the magnetic fieldat its centre is

State the Biot-Savart's law for the magnetic field due to a current carrying element. Use this law to obtain a formula for magnetic field at athe centre of circular loop of radius r carrying steady current I . Sketch the magnetic field lines for a current loop clearly indicating the direction of the field.

Two long straight, current-carrying conductors , PQ and XY, are held a constant distance apart as shown in the figure. The conductors carry the magnitude of current in the same direction . A plan view form above the conductors is shown in the figure. Draw arrows, one in each case, to show the direction of the magnetic field at Q due to the current in wire XY. the force at Q as a result of the magnetic field due to the current in wire XY.

A long solenoid carrying a current produces a magnetic field B along its axis. If the number of turns per cm is doubled and the current in the solenoid is halved, then the new value of the magnetic field along its axis will be

Derive an expression for the magnetic field.at the centre of a current carrying coil.

A circular coil of 300 turns and diameter 14 cm carries a current of 15 A. what is the magnitude of magnetic moment associated with the coil?