Thursday, 24 July 2025

Week 2 Term 3 2025 Internal Resistance of a Battery & Kirchhoff's Laws

  Homework

  • Act 13A, p.205-206 Level 2 D.C. Circuit Revision
  • Act 13B, p.210-211 Internal Resistance of a Battery
  • Ex 6A, p.251-253 Resistor Networks
  • Ex 6B, P.261-262 Internal Resistance of a Battery

  • 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


    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
  • Tuesday, 24 June 2025

    Week 9 Term 2 2025 Simple Harmonic Motion (S.H.M.)

      Homework:

    2D Momentum and Centre of Mass C.O.M.
    • Ex 4A, p.100-102, C.O.M.
    • Ex 4B, p.108-112, Momentum & C.O.M. in 1D
    • Ex 4C, p.116-122, Momentum & C.O.M. in 2D
    • Act 7A, p.87-88 Motion, Force and Energy
    • Act 7B, p.91-92 Impulse
    • Act 7C, p.95-96 Conservation of Momentum
    • Act 7D, p.100-101 C.O.M.

    Circular Motion
    • Act 8A, p.120-121 Horizontal Circles and Banked Corners
    • Act 8B, p.124-125 Vertical Circles
    • Act 8C, p.129 Sattelites
    • Ex 4D, p.128-131, Banked Corners (Circular Motion)
    • Ex 4E, p.138-142, Vertical Circles
    • Ex 4F, p.145-147, Gravity
    • Ex 4G, p.153-156 Satallites

    Rotational Motion

    • Act 9A, p. 139-140, Angular Motion

    • Act 9B, p. 144-145, Torque - Rotational Inertia

    • Act 9C, p.149-150, Angular Momentum

    • Act 9D, p.153-154 Rotational Kinetic Energy

    • Ex 4H, p.160-162, Rotational Kinematics

    • Ex 4H, p.160-162, Rotational Kinematics

    • Ex 4I, P.167-171, Rotational Force & Momentum

    • Ex 4J, p.175-177, Rotational Kinetic Energy


    Simple Harmonic Motion
    • Act 10A, p. 148, Simple Harmonic Motion (SHM)
    • Act 10B, p.153, Reference CIrcle
    • Act 10C, p. 158-160, SHM - displacement, velocity, acceleration
    • Act 10D, p. 164-165, Springs and Pendulums
    • Act 10E, p. 172, SHM Energy, Damped, Driven, Resonance
    • Ex 4K, p.184-187, Pendulums and Bouncing Springs
    • Ex 4L, p.191-194, SHM

    Simple Harmonic Motion - SHM






    SHM

    Simple Harmonic Motion: Crash Course Physics

    Pendulum Wave Demonstration





    SHM & Energy


    Energy of Simple Harmonic Oscillators

    Damped SHM

    Damping of Simple Harmonic Motion

    Damped SHM & Resonance


    Tacoma Bridge Collapse




    Tuesday, 10 June 2025

    Week 7 Term 2 2025 Rotaional Motion

     

     Homework:

    C.O.M. & 2D momentum

    • Ex 4A, p.100-102, C.O.M.
    • Ex 4B, p.108-112, Momentum & C.O.M. in 1D
    • Ex 4C, p.116-122, Momentum & C.O.M. in 2D
    • Act 7A, p.87-88 Motion, Force and Energy
    • Act 7B, p.91-92 Impulse
    • Act 7C, p.95-96 Conservation of Momentum
    • Act 7D, p.100-101 C.O.M.

    Circular Motion
    • Act 8A, p.120-121 Horizontal Circles and Banked Corners
    • Act 8B, p.124-125 Vertical Circles
    • Act 8C, p.129 Sattelites
    • Ex 4D, p.128-131, Banked Corners (Circular Motion)
    • Ex 4E, p.138-142, Vertical Circles
    • Ex 4F, p.145-147, Gravity
    • Ex 4G, p.153-156 Satallites

    Rotational Motion
    • Act 9A, p. 139-140, Angular Motion
    • Act 9B, p. 144-145, Torque - Rotational Inertia
    • Act 9C, p.149-150, Angular Momentum
    • Act 9D, p.153-154 Rotational Kinetic Energy
    • Ex 4H, p.160-162, Rotational Kinematics
    • Ex 4I, P.167-171, Rotational Force & Momentum
    • Ex 4J, p.175-177, Rotational Kinetic Energy
    Rotational Inertia



    Rotational Inertia

    Torque


    Angular Momentum

    Angular Momentum - Sixty Symbols

    Gyroscopic Precession



    Slow Motion Flipping Cat Physics



    Counter Steering Physics




    The Bizarre Behavior of Rotating Bodies, Explained


    Ellipzoids and the Bizarre Behavior of Rotating Bodies



    Thursday, 29 May 2025

    Week 5 Term 2 2025 Rotational Kinematics

     Homework:

    C.O.M. & 2D momentum

    • Ex 4A, p.100-102, C.O.M.
    • Ex 4B, p.108-112, Momentum & C.O.M. in 1D
    • Ex 4C, p.116-122, Momentum & C.O.M. in 2D
    • Act 7A, p.87-88 Motion, Force and Energy
    • Act 7B, p.91-92 Impulse
    • Act 7C, p.95-96 Conservation of Momentum
    • Act 7D, p.100-101 C.O.M.

    Circular Motion
    • Act 8A, p.120-121 Horizontal Circles and Banked Corners
    • Act 8B, p.124-125 Vertical Circles
    • Act 8C, p.129 Sattelites
    • Ex 4D, p.128-131, Banked Corners (Circular Motion)
    • Ex 4E, p.138-142, Vertical Circles
    • Ex 4F, p.145-147, Gravity
    • Ex 4G, p.153-156 Satallites

    Rotational Motion
    • Act 9A, p. 128-129, Angular Motion
    • Ex 4H, p.160-162, Rotational Kinematics

    Radians

    Radian Measure is used so that we can easily calculate an arc length, d (m), given an angle, 𝛉 (Rad) and the radius, r (m).

    d = r𝛉

    This in turn allows us to relate velocity, v (ms-1) to angular velocity ⍵ (rads-1), in the same way. Note that Angular Velocity may also be called Angular Frequency.

    v = r⍵, 

    also ⍵ = 2𝝅f

     This also allows us to relate acceleration, a (ms-2), to angular acceleration, α (rads-2), in the same way.

    a = rα

    The rotational kinematics work just like the translational kinematic equations when there is a constant acceleration.


    Rotational Kinematics Review

    Rotational Kinematics



    Rotational Kinematics Physics: Problems, Basic Introduction, Equations & Formulas



    Rotational Motion Physics, Basic Rotational Motion Physics: Introduction, 

    Angular Velocity & Tangential Acceleration

    Thursday, 8 May 2025

    Week 2 Term 2 2025 Circular Motion - Banked Corners - Vertical Circles - Satellites

     Homework:

    C.O.M. & 2D momentum

    • Ex 4A, p.100-102, C.O.M.
    • Ex 4B, p.108-112, Momentum & C.O.M. in 1D
    • Ex 4C, p.116-122, Momentum & C.O.M. in 2D
    • Act 7A, p.87-88 Motion, Force and Energy
    • Act 7B, p.91-92 Impulse
    • Act 7C, p.95-96 Conservation of Momentum
    • Act 7D, p.100-101 C.O.M.

    Circular Motion
    • Act 8A, p.120-121 Horizontal Circles and Banked Corners
    • Act 8B, p.124-125 Vertical Circles
    • Act 8C, p.129 Sattelites
    • Ex 4D, p.128-131, Banked Corners (Circular Motion)
    • Ex 4E, p.138-142, Vertical Circles
    • Ex 4F, p.145-147, Gravity
    • Ex 4G, p.153-156 Satallites

    Banked Corners

    Circular Motion - Banked Curves


    Car on a Banked Corner

    Free body diagram sine and cosine components



    Vertical Circular Motion

    Vertical Circular Motion

    PhET - Gravity Force Lab



    Gravitation: The Four Fundamental Forces of Physics



    Introduction to Newton's law of gravitation | Physics | Khan Academy


    Speed of a Satellite in Circular Orbit, Orbital Velocity, Period, Centripetal Force


    Gravity Visualised

    How Do Satellites Get & Stay in Orbit?


    Kepler’s First Law of Motion - Elliptical Orbits 

    Kepler’s Second Law of Motion - Equal Area Equal Time Law


    Kepler's Third Law of Motion - T2 ∝ R3