Electrons, Photons & Waves

•Explain that electric current is a net flow of charged particles.

•Explain that electric current in a metal is due to the movement of

electrons, whereas in an electrolyte the current is due to the movement

of ions.

•Explain what is meant by conventional current and electron flow.

•Select and use the equation ΔQ = IΔt.

•Define the coulomb.

Module 1 Electric Current

Electrons, Photons & WavesModule 1 Electric Current

Electrons, Photons & WavesModule 1 Electric Current

Electrons, Photons & WavesModule 1 Electric Current

Electrons, Photons & WavesModule 1 Electric Current

Q = I x t

Electrons, Photons & WavesModule 1 Electric Current

The Coulomb One coulomb is the total charge supplied by a current of one ampere in a time of one second.

Electrons, Photons & WavesModule 1 Electric Current

•Recall and use the elementary charge e = 1.6 × 10-19 C.•Describe Kirchhoff’s first law and appreciate that this is a consequence of conservation of charge.•State what is meant by the term mean drift velocity of charge carriers.•Select and use the equation I = Anev.•Describe the difference between conductors, semiconductors and insulators in terms of the number density n.

Series Circuits

A1

A3

A2

V1 V2

Same Value Resistors

Electrons, Photons & Waves

Series Circuits

A1

A3

A2

V1 V2

Different Value Resistors

Parallel Circuits

A3

A2

A1

V1

Same Value Resistors

V2

Parallel Circuits

A3

A2

A1

V1

Different Value Resistors

V2

Drift Velocity

• state what is meant by the term mean drift velocity of charge carriers;• select and use the equation I = Anev;• describe the difference between conductors, semiconductors and insulators in terms of the number density n.

Drift Velocity

Drift Velocity

The mean drift velocity is the average displacement travelled by the electrons along the wire per second;

I = Anev

Drift Velocity I = Anev