Term 3 Week 10 2019

Homework

Ex 6A, p.251-254 Level 2 D.C. Circuit Revision

Ex 6B, p.261-261 Internal Resistance of a Battery

Ex 6C, p.267-272 Kirchhoff's Laws

Ex 6D, p.277-280 Capacitors Ep = ½ QV

Ex 6E, p.283-284 Capacitors C = 𝜺r𝜺oA/d

Ex 6F, p.289-292 Capacitor Networks (Series & Parallel)

Ex 6G, p.298-300 Capacitor Charge & Discharge

Ex 6H, p.303-305 Inductance in D.C. Circuits

Ex 6I, p.308-310 Inductors Charge & Discharge

Ex 6J, p.311-312 Transformers

Ex 6K, p.314-315 A.C. Peak and r.m.s.

Ex 6L, p.316-317 A.C. Capacitor Reactance

Ex 6M, p.319-320 A.C. Inductor Reactance

Ex 6N, 321-324 A.C. RCL Impedance

Faradays Law PhET Application

RCL Phase Relationships

MIT Mathlet on RCL Phase Relationships - Interactive

UNSW Animations for RCL Phase Relationships

Impedance of a Capacitor Resistor Circuit

Z = √(XC2 + R2)

θ = tan-1(-XC/R) = tan-1(-VC/VR)

The Capacitor Reactance is 90° behind the Resistance

The Capacitor Voltage is 90° behind the Resistor Voltage

Impedance of a Inductor Resistor Circuit

Z = √(XL2 + R2)

θ = tan-1(XL/R) = tan-1(VL/VR)

The Inductor Reactance is 90° ahead of the Resistance

The Inductor Voltage is 90° ahead of the Resistor Voltage

Impedance of a RCL Circuit

Z = √((XL - XC)2+ R2)

θ = tan-1((XL - XC)/R) = tan-1((VL - VC)/VR)

Resonance

A.C. Circuits & Resonance

MIT Physics Demo -- Resonant RLC Circuit

Term 3 Week 7 2019

Homework

Ex 6A, p.251-254 Level 2 D.C. Circuit Revision

Ex 6B, p.261-261 Internal Resistance of a Battery

Ex 6C, p.267-272 Kirchhoff's Laws

Ex 6D, p.277-280 Capacitors Ep = ½ QV

Ex 6E, p.283-284 Capacitors C = 𝜺r𝜺oA/d

Ex 6F, p.289-292 Capacitor Networks (Series & Parallel)

Ex 6G, p.298-300 Capacitor Charge & Discharge

Ex 6H, p.303-305 Inductance in D.C. Circuits

Ex 6I, p.308-310 Inductors Charge & Discharge

Ex 6J, p.311-312 Transformers

Right Hand Screw Rule

Right Hand Slap Rule

Magnetic Flux

Faraday's Law - PhET Application

Lenz's Law

Faraday;'s Law & Lenz's Law

Inductance

Inductor PhET Demonstration

Transformers

The ratio of the secondary to primary voltage is equal to the ratio of the secondary to primary turns

Vs/Vp = Ns/Np

In an Ideal Transformer 

Secondary Power = Primary Power

In reality, energy is lost through heat from eddy currents generated in the soft iron core from the changing flux.

NB: As Voltage is often referred to as e.m.f. the Symbol "e" or "E" is often used in engineering to refer to e.m.f.

This is the case in the video below.

After explaining how basic Transformers work, this video goes on to explain 3-Phase Transformers.

NZ Street Step-Down Transformer

Internal Diagram of a Transformer

Faraday Cage

Tesla Coil & Faraday Cage

Exploding Cans with Electromagnets

Levitating with Electromagnets

Term 3 Week 3 2019

Homework

Ex 6A, p.251-254 Level 2 D.C. Circuit Revision

Ex 6B, p.261-261 Internal Resistance of a Battery

Ex 6C, p.267-272 Kirchhoff's Laws

Ex 6D, p.277-280 Capacitors Ep = ½ QV

Ex 6E, p.283-284 Capacitors C = 𝜺r𝜺oA/d

Ex 6F, p.289-292 Capacitor Networks (Series & Parallel)

Ex 6G, p.298-300 Capacitor Charge & Discharge

Capacitor

C = Q/V

Capacitors

Basic Definition

Physical Parameters

Energy Stored

Ep = ½ QV

Capacitors & Capacitance

Dielectric

An insulating material placed in between the capacitor plates to increase the Capacitance

C = 𝜺r𝜺oA/d

Dielectrics in Capacitors

PhET Capacitor Lab Basics - App

Capacitor Circuits

Capacitors in Series

Calculating Voltage Charge and Total Capacitance

Capacitors in Parallel

Calculating Voltage Charge and Total Capacitance

Capacitors in Parallel vs Capacitors in Series

Capacitors in Combination

Series & Parallel Capacitors

Capacitors in Combination

Patrallel & Series Capacitors

Capacitors in Series

Calculating Voltage Drop

Capacitors in Series

Calculating the Charge Stored

Capacitors in Series

Calculating the Equivalent Capacitance

Capacitors in Parallel

Calculating Voltage Drop

Capacitors in Parallel

Calculating the Charge Stored

Capacitors in Parallel

Calculating the Equivalent Capacitance

Capacitor Charge & Discharge

RC Circuits 1: Charging and Discharging a Capacitor

Term 3 Week 2 2019

Homework

Ex 6A, p.251-254 Level 2 D.C. Circuit Revision

Ex 6B, p.261-261 Internal Resistance of a Battery

Ex 6C, p.267-272 Kirchhoff's Laws

Electrical Charge

Current

Current is the rate of flow of Charge

I = Δq/Δt

Current

Voltage

Voltage (Potential Difference) is the change in energy (work done) to each coulomb of charge between two points on a circuit, or two points across an electric field

Voltage

Voltage (Potential Difference) is the change in energy (work done) to each coulomb of charge between two points on a circuit, or two points across an electric field

V = ΔE/Q

Ohm's Law & Resistance

Power

Circuit Symbols

Ohm's Law

Ohm's Law - PhET App

D.C. Circuit Construction Kit - PhET App

Ohm's Law

Internal Resistance of a Battery

Batteries can be thought of as having an ideal voltage supply E.M.F. (Electromotive Force) in series with an internal resistance

V = 𝛆 - Ir

How to find the internal resistance of a

battery

Kichhoff's Laws

Kirchhoff’s Current Law
“At any junction in a circuit, the total current entering the junction equals the total current leaving the junction”
Kirchhoff’s Voltage Law
“Around any closed path of a circuit, the total of all the potential differences, V, is zero”

Kirchhoff's Rules for Circuit Analysis - Explanation

Kirchhoff's Rules for Circuit Analysis - Example 1

Kirchhoff's Rules for Circuit Analysis - Example 2

Kirchhoff's Rules for Circuit Analysis - Example 3