Electrons, Photons & Waves

1. Module 1 Electric Current 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.

2. Module 1 Electric Current Electrons, Photons & Waves

3. Module 1 Electric Current Electrons, Photons & Waves

4. Module 1 Electric Current Electrons, Photons & Waves

5. Module 1 Electric Current Electrons, Photons & Waves Q = I x t

6. Module 1 Electric Current Electrons, Photons & Waves The Coulomb One coulomb is the total charge supplied by a current of one ampere in a time of one second.

7. Module 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. Electrons, Photons & Waves

8. Electrons, Photons & Waves Series Circuits Same Value Resistors A3 A1 A2 V1 V2

9. Series Circuits Different Value Resistors A3 A1 A2 V1 V2

10. Parallel Circuits Same Value Resistors A3 A1 V1 A2 V2

11. Parallel Circuits Different Value Resistors A3 A1 V1 A2 V2

12. 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.

13. Drift Velocity

14. Drift Velocity The mean drift velocity is the average displacement travelled by the electrons along the wire per second; I = Anev

15. Drift Velocity I = Anev