Question

What is the S.I. unit for mutual inductance?

Answer 1

The SI unit for mutual inductance is the henry (H). It’s the same unit used for inductance in general. One henry is defined as the amount of mutual inductance required to induce an electromotive force of one volt when the current in one coil changes at a rate of one ampere per second.

Answer 2

The S.I. unit for mutual inductance is the **henry** (symbol: **H**).

To explain in detail:

- **Mutual Inductance** is a measure of how much one coil (or circuit) induces an electromotive force (EMF) in another coil (or circuit) when the current in the first coil changes. It quantifies the efficiency with which the magnetic field created by one coil induces a voltage in the second coil.

- The unit of inductance, including mutual inductance, is the henry. One henry is defined as the amount of mutual inductance between two coils when a change of one ampere per second in the current in the first coil induces a voltage of one volt in the second coil.

In equation form, mutual inductance \( M \) is related to the induced voltage \( V \) and the rate of change of current \( \frac{dI}{dt} \) in the following way:

\[ V = -M \frac{dI}{dt} \]

where:
- \( V \) is the induced voltage in volts (V),
- \( M \) is the mutual inductance in henries (H),
- \( \frac{dI}{dt} \) is the rate of change of current in amperes per second (A/s).

In summary, mutual inductance is measured in henries, just like self-inductance, which describes a similar phenomenon within a single coil rather than between two coils.