topic 2: electromagnetism

define coloumbs law

two stationary electric charges exert a force on one another

define electric field

electric field is a region of space surrounding an electrically charged particle that exerts a force on other charged particles, either repelling or attracting them.

define electric field strength 

the intensity of an electric field at a particular location within the field

define electrical potential energy

the energy a charged particle possesses by virtue of its location within an electric field or relative to other charged particles

define the term magnetic field

the region of space near a magnet, electric current or moving electrically charged particles in which a magnetic force acts on any other magnet, electric current or moving electrically charged particles

define magnetic flux

a measurement of the total magnetic field that passes through a given area

define magnetic flux density

the strength of a magnetic field or the number of magnetic field lines per unit area

define electromagnetic induction

the production of an electromotive force(EMF) or voltage across an electrical conductor due to its dynamic interaction with a magnetic field

define electromotive force

a difference in potential that lead to the production of an electric current

define faradays law

a changing magnetic field creates an electromotive force in a conductor that can drive an electric current if the circuit is closed

define Lenz’s law

an induced current will create a magnetic field that opposes the change in magnetic flux

explain how transformers work in terms of faradays law and electromagnetic induction

Transformers work on the principle of electromagnetic induction as described by Faraday’s Law. When alternating current flows through the primary coil, it produces a changing magnetic field in the core. This changing magnetic flux induces an electromotive force (EMF) in the secondary coil. The voltage induced depends on the rate of change of magnetic flux and the number of turns in each coil, allowing the transformer to step voltage up or down.

explain how Lenz’s law is consistent with the principle of conservation of energy

As a magnet is pushed toward a coil, mechanical energy from the force applied to move the magnet is used to change the magnetic flux through the coil. According to Lenz’s Law, the induced current generates a magnetic field that opposes the motion of the magnet, creating a resistive magnetic force. The mechanical energy from pushing the magnet is required to overcome this resistance and is converted into electrical energy in the coil, as current. This ensures that energy from the current is not created from nothing, upholding the principle of conservation of energy.

define and explain electromagnetic radiation in terms of electric fields and magnetic fields

Electromagnetic radiation is energy that travels through space as oscillating electric and magnetic fields. It is produced when an electric charge accelerates, creating a changing electric field that induces a changing magnetic field, and vice versa. These fields are perpendicular to each other and to the direction of wave propagation, allowing the wave to self-sustain and move through space.