Wednesday, 21 August 2024

Week 5 Term 3 2024 AC Electricity

Homework

Basic Circuit Revision

  • Act 13A, p.205-206 Level 2 D.C. Circuit Revision


Internal Resistance of a Battery

  • Act 13B, p.210-211 Internal Resistance of a Battery

  • Ex 6B, P.261-262 Internal Resistance of a Battery


Resistor Networks (Resistors in Series and Parallel)

  • Ex 6A, p.251-253 Resistor Networks


Kirchhoff’s Laws

  • Act 13C, p.214-216 Kirchhoff's Laws

  • Ex 6C, p.267-272 Kirchhoff's Laws


Capacitors

  • Act 14A, p.240 Capacitance & Capacitors

  • Act 14B, p.244-245 Capacitor Networks & Energy

  • Act 14C, p.249-251 Charging & Discharging Capacitors

  • Ex 6D, p.277-280 Capacitor Energy

  • Ex 6E, p.283-284 Capacitors

  • Ex 6F, p.289-292 Capacitor Networks

  • Ex 6G, p.298-300 Charging & Discharging Capacitors


Inductors

  • Act 15A, p.259-260 Induced Voltage & Current

  • Act 15B, p.263-264 Transformers

  • Act 15C, p.268-269 Inductance

  • Act 15D, p.272-273 Voltage and Current Graphs for the Inductor

  • Ex 6H, p.303-305 Inductance in DC Circuits

  • Ex 6I, 308-310 Inductance: Self; Mutual; Time Constant; Energy Stored

  • Ex 6J, p.311-312 Transformers


AC Electricity

  • Act 16A, p.265-266 Peak and rms voltage and current

  • Act 16B, p.260 Capacitor Reactance

  • Act 16C, p.275-276 Voltage and Current in a RC circuit

  • Act 16D, p.279 Voltage Current and Impedance in a RC circuit

  • Act 16E, p.282 Inductor Reactance

  • Act 16F, p.286-287 Voltage Current and Impedance in a RL circuit

  • Act 16G, p.289 The LCR series circuit

  • Act 16H, 293-296 Resonance

  • Ex 6L, p.316-317, RC Circuits

  • Ex 6M, 319-320, LC Circuits

  • Ex 6N, 321-324, LCR Circuits


Capacitor Reactance

Inductor Reactance

Resistors in AC Circuits

Capacitors in AC Circuits

Inductors in AC Circuits

RCL in AC Circuits - Part 1

RCL in AC Circuits - Part 2

Capacitors in AC Circuits - Part 3

Inductors in AC Circuits - Part 3

RC in AC Circuits - Part 4

RL in AC CIrcuits - Part 4

RCL in AC Circuits - Part 3

Summary of RCL Circuits

RCL Resonance


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


Understanding Inductance and Back EMF



A.C. Circuits & Resonance





Tuesday, 13 August 2024

Week 3 Term 3 2024 Inductors

 Basic Circuit Revision

  • Act 13A, p.205-206 Level 2 D.C. Circuit Revision


Internal Resistance of a Battery

  • Act 13B, p.210-211 Internal Resistance of a Battery

  • Ex 6B, P.261-262 Internal Resistance of a Battery


Resistor Networks (Resistors in Series and Parallel)

  • Ex 6A, p.251-253 Resistor Networks


Kirchhoff’s Laws

  • Act 13C, p.214-216 Kirchhoff's Laws

  • Ex 6C, p.267-272 Kirchhoff's Laws


Capacitors

  • Act 14A, p.240 Capacitance & Capacitors

  • Act 14B, p.244-245 Capacitor Networks & Energy

  • Act 14C, p.249-251 Charging & Discharging Capacitors

  • Ex 6D, p.277-280 Capacitor Energy

  • Ex 6E, p.283-284 Capacitors

  • Ex 6F, p.289-292 Capacitor Networks

  • Ex 6G, p.298-300 Charging & Discharging Capacitors


Inductors

  • Act 15A, p.259-260 Induced Voltage & Current

  • Act 15B, p.263-264 Transformers

  • Act 15C, p.268-269 Inductance

  • Act 15D, p.272-273 Voltage and Current Graphs for the Inductor

  • Ex 6H, p.303-305 Inductance in DC Circuits

  • Ex 6I, 308-310 Inductance: Self; Mutual; Time Constant; Energy Stored

  • Ex 6J, p.311-312 Transformers


Right Hand Screw Rule


Right Hand Slap Rule

Magnetic Flux










Lenz's Law

Faraday's Law & Lenz's Law


Inductance








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 Transforme
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

How Do Substations Work?

Fuse MCB, How it Works