Question

How can you verify right hand thumb rule experimentally?
(A). Using iron filings in a magnetic field
(B). Using bar magnet in a magnetic field
(C). Using a dead wire no current in a magnetic field
(D). Using capacitors in a magnetic field

Answer 1

Hint: Magnetic field is a vector that describes the influence of magnets or magnetic materials. Different magnetic materials have different magnetic fields around them. The right hand thumb rule gives us the direction of the magnetic field around a straight wire; it can be used to visualize the magnetic lines of forces about a straight wire.

Complete answer:
As we know that when current flows through a straight wire, a magnetic field is developed around it which is circular in shape. The direction of the magnetic field around the wire can be perfectly visualized using right hand thumb rule.
According to the right hand thumb rule, if the thumb represents the flow of current in a straight wire then the curled fingers will represent the direction of magnetic lines of forces around the wire.
The right hand thumb rule can be verified experimentally by the following experiment.
Bring a magnet near a wire carrying current. Since there is a magnetic field due to current in the wire, the magnet will align itself such that magnetic lines of forces come out the north pole and enter back into the magnet from the south pole. Similarly, the right hand thumb rule gives us the same result for magnetic fields around the wire.
This experiment is very similar to the Oersted experiment.
Therefore, we can verify right hand thumb rule experimentally using a magnet in a magnetic field.

Hence the correct option is (B).

Note:
In the Oersted experiment, a compass is kept near a circuit. When current flows through the circuit, the needle of the compass deflects and when the direction of current was reversed, the compass needle deflects in the opposite direction. The magnetic lines of forces are imaginary lines about a magnetic material which represent the direction of magnetic field around the material.