Energy in a current-carrying coil is stored in the form of a magnetic field.

Explanation:
When a current flows through a coil, it creates a magnetic field around the coil. This magnetic field contains energy, which is stored in the coil. The energy stored in the magnetic field is given by the formula:

E = (1/2) * L * I^2

Where E is the energy stored, L is the inductance of the coil, and I is the current flowing through the coil. The inductance of a coil depends on factors such as the number of turns in the coil, the area of the coil, and the magnetic permeability of the material within the coil.

The magnetic field stores energy because it has the ability to do work. This can be seen when the current in the coil is changed. According to Faraday's law of electromagnetic induction, a changing magnetic field induces an electromotive force (EMF) in a nearby conductor. This induced EMF can cause a current to flow in the conductor, allowing the magnetic field to do work.

The energy stored in the magnetic field of a coil can be transformed into other forms, such as electrical energy, by connecting the coil to a load. When the coil is connected to a load, the changing magnetic field induces a current in the load, allowing the energy stored in the magnetic field to power the load.

In summary, energy in a current-carrying coil is stored in the form of a magnetic field. The magnetic field contains energy that can be transformed into other forms, such as electrical energy, by inducing a current in a nearby conductor.