Answer and Explanation:
An electromagnet is made up of a coil of wire through which an electric current flows. When an electric current flows through the wire, it creates a magnetic field around the wire. The magnetic field is created because the moving electrons in the wire produce a magnetic field, as described by the right-hand rule.
When an electromagnet is placed in a magnetic field, the magnetic field produced by the current in the wire interacts with the external magnetic field. This interaction causes a force to be exerted on the wire, which causes the wire to move. The force is proportional to the strength of the magnetic field and the current flowing through the wire. This is the principle behind how an electromagnet can act like a loop of wire in a magnetic field.
In a galvanometer, an electromagnet is used to create a magnetic field that interacts with the magnetic field produced by the current flowing through the circuit. This interaction causes a force to be exerted on the wire in the electromagnet, which in turn moves the pointer of the galvanometer. The greater the current flowing through the circuit, the greater the force exerted on the wire in the electromagnet, and the greater the deflection of the pointer.