Question

By using the given experimental set-up, how can it be shown that:
A force is exerted on the current-carrying conductor AB when it is placed in a magnetic field.
The direction of the force can be reversed in two ways.

Hint:

The direction of force on a current-carrying conductor in a magnetic field can be reversed by changing either the direction of the current or the magnetic field.

Answer 1

(a) A force on the current-carrying conductor: The force on the conductor AB is shown experimentally using a simple setup, as shown in the figure. The magnetic field is applied by a magnet (N and S poles), and a current is passed through the conductor AB. When the current-carrying conductor is placed in a magnetic field, a force is exerted on the conductor due to the interaction between the current in the conductor and the magnetic field. This force is given by: \[ F = BIL \sin \theta \] where:
\( F \) is the force on the conductor,
\( B \) is the magnetic field strength,
\( I \) is the current in the conductor,
\( L \) is the length of the conductor in the magnetic field,
\( \theta \) is the angle between the magnetic field and the current direction.
(b) Reversing the direction of force: The direction of the force on the conductor can be reversed by either: 
1. Reversing the direction of the current in the conductor AB. 
2. Reversing the direction of the magnetic field (by reversing the poles of the magnet).