Lenz

Definition

Lenz's Law states that the direction of an induced current in a conductor due to a changing magnetic field is such that it creates a magnetic field opposing the change. This law ensures the conservation of energy in electromagnetic systems.

5 Must Know Facts For Your Next Test

1. Lenz's Law can be mathematically expressed as $\mathcal{E} = -\frac{d\Phi_B}{dt}$, where $\mathcal{E}$ is the electromotive force and $\Phi_B$ is the magnetic flux.
2. It is a fundamental principle in electromagnetic induction, ensuring that induced currents oppose their cause.
3. Lenz's Law is derived from Faraday's Law of Induction and the negative sign indicates opposition to change.
4. The law plays a crucial role in the operation of devices like electric generators and transformers.
5. Lenz's Law ensures compliance with the conservation of energy by preventing perpetual motion.

Review Questions

• What does Lenz's Law say about the direction of induced current?
• How does Lenz's Law relate to Faraday's Law of Induction?
• Why is Lenz's Law important for ensuring the conservation of energy?

Related terms

Faraday's Law of Induction: States that a changing magnetic field through a loop induces an electromotive force (EMF) proportional to the rate of change of magnetic flux.

Electromotive Force (EMF):

The voltage generated by either electrochemical or electromagnetic means, driving current flow in a circuit.

Magnetic Flux: A measure of the quantity of magnetism, considering both the strength and extent of a magnetic field.