Monday, 29 May 2023

Week 5 Term 2 2023

 Homework

  • Act 15A, p.173-176 Models of the Atom and Radioactivity
  • Ex 5A, p. 151-155 Models of the Atom
  • Ex 5B, p.160-171 Radioactivity


Models of the Atom


History of the Atom

Models of the Atom Timeline



Discovery of the Electron: Cathode Ray Tube Experiment


Discovery of the Nucleus: Rutherford's Gold Foil Experiment


Charge of an Electron: Millikan's Oil Drop Experiment


Atomic Structure: Discovery of the Neutron


Parts of the Atom


Isotopes
Isotopes are versions of an atom or an element that have the same number of protons, but different numbers of neutrons



What are Isotopes?




Radioactive Decay
Alpha, Beta & Gamma Radiation



  • Alpha particles are emitted by a larger nucleus that has too many Protons
  • Beta particles are emitted by a nucleus that has too many Neutrons
  • Gamma photons are emitted by a nucleus that has too much Energy (is in an exited state)





Alpha Decay

Beta Decay


Radiation

Types of Radiation



Is radiation dangerous?

The Most Radioactive Places on Earth

Millisieverts and Radiation - Sixty Symbols




Half Life Calculations



Tuesday, 9 May 2023

Week 3 Term 2 2023

 Homework

  • Act 8B Graphs of motion p.101
  • Act 8C Kinematics p.102
  • Ex 4E Kinematics p.115-117
  • Act 12B Projectile Motion p.140-141
  • Ex 4F Projectile Motion p.119-124
  • Act 9A Vectors p.108-109
  • Ex 4A Vectors p. 90-94
  • Act 10A Forces p.117-118
  • Act 10B Forces p.123-124
  • Ex 4B Forces p.97-104
  • Act 13A p.148-149 Circular Motion
  • Ex 4H p.132-134 Circular Motion
  • Ex 2B, p.16-18, Graphing
  • Ex 2C, p.19-25, Identifying Relationships and Experimental Equations
  • Ex 2B, p.23-40, Level 3 Handout booklet on Graphing Errors
  • Act 14B, p. 158-160 Combined Mechanics
  • Ex 4J, p. 143-147 Energy, Work, Power
  • Act 11A, p.130, Momentum and Impulse
  • Act 11B, p. 133-134, Collisions
  • Ex 4D, p.108-112, Momentum P = mv
  • Ex 4C, p.105-107, Impulse ΔP = FΔt
  • Act 10B, p.123-124, Torque
  • Ex 4G p.125-130 Torque

    Torque
    𝝉 = F L⦜
    𝝉: Torque (Nm)
    F: applied Force (N)
    L⦜: Length of lever at right angles to the applied force (m)

    • Torque (Moments) in Level 2 Physics will involve Static Systems
    • Therefore the Torques are balanced and the Forces are balanced - Newton's Laws of Motion apply to turning forces as well as linear forces
    • PhET - Torque Balancing Act simulation



    Bridge support forces moments


    Torque (Moments anout a point)
    Static (unmoving) systems will be used for this section. Therefore all forces, linear and turning, are balanced





    Torque

Torque and Equilibrium


Monday, 1 May 2023

Week 2 Term 2 2023

 Homework

  • Act 8B Graphs of motion p.101
  • Act 8C Kinematics p.102
  • Ex 4E Kinematics p.115-117
  • Act 12B Projectile Motion p.140-141
  • Ex 4F Projectile Motion p.119-124
  • Act 9A Vectors p.108-109
  • Ex 4A Vectors p. 90-94
  • Act 10A Forces p.117-118
  • Act 10B Forces p.123-124
  • Ex 4B Forces p.97-104
  • Act 13A p.148-149 Circular Motion
  • Ex 4H p.132-134 Circular Motion
  • Ex 2B, p.16-18, Graphing
  • Ex 2C, p.19-25, Identifying Relationships and Experimental Equations
  • Ex 2B, p.23-40, Level 3 Handout booklet on Graphing Errors
  • Act 14B, p. 158-160 Combined Mechanics
  • Ex 4J, p. 143-147 Energy, Work, Power
  • Act 11A, p.130, Momentum and Impulse
  • Act 11B, p. 133-134, Collisions
  • Ex 4D, p.108-112, Momentum P = mv
  • Ex 4C, p.105-107, Impulse ΔP = FΔt

Momentum

Conservation of Momentum
In the absence of external forces the total momentum of a system is always conserved

Impulse
The change in Momentum for a single object
ΔP = Pf - Pi
&
ΔP = FΔt
&
ΔP = mΔv
  • The unis are eithor Ns or kgms-1 , this is the same unit and the one that is used depends on the context
  • Impulse on one object is always equal and opposite to the impulse on the other onject - Newton's Third Law



Physics of Car Crashes (Impulse)

Impulse


Impulse


Impulse examples///Homemade Science with Bruce Yeany



Momentum

Impulse

Monday, 20 March 2023

Week 8 Term 1 2023

 Homework

  • Act 8B Graphs of motion p.101
  • Act 8C Kinematics p.102
  • Ex 4E Kinematics p.115-117
  • Act 12B Projectile Motion p.140-141
  • Ex 4F Projectile Motion p.119-124
  • Act 9A Vectors p.108-109
  • Ex 4A Vectors p. 90-94
  • Act 10A Forces p.117-118
  • Act 10B Forces p.123-124
  • Ex 4B Forces p.97-104
  • Act 13A p.148-149 Circular Motion
  • Ex 4H p.132-134 Circular Motion
  • Ex 2B, p.16-18, Graphing
  • Ex 2C, p.19-25, Identifying Relationships and Experimental Equations
  • Ex 2B, p.23-40, Level 3 Handout booklet on Graphing Errors
  • Act 14B, p. 158-160 Combined Mechanics
  • Ex 4J, p. 143-147 Energy, Work, Power

Energy
  • Energy can never be created
  • Energy can never be destroyed
  • Energy can only change its form (Work is done)
  • Energy has the ability to make something happen, i.e. to do Work
  • The unit for energy is the Joule (J)
  • J = Kgm2s-2  in fundamental units

Perpetual Motion Machine?

A Simple Proof of Conservation of Energy


Conservation of Energy


Work & Transformation of Energy



Power & Work Done

Kinetic Energy


Gravitaional Potential Energy



Work, Energy, and Power

Work, Energy and Power Review


Gravitational Potential Energy and Kinetic Energy Skate Park PhET Link - HTML


Work
Work is a transformation (change) of energy from one form to another form. Work only occurs when something is done.

  • Power is the rate at which energy is transformed
  • Power is the rate at which work is done
  • Unit of power Watt (W = J/s)
Power vs Energy

Work, Energy & Power



Kinetic Energy & Gravitational Potential Energy

World's Heaviest Weight - the importance of error reduction through measurement

Sunday, 12 March 2023

Week 7 Term 1 2023

 Homework

  • Act 8B Graphs of motion p.101
  • Act 8C Kinematics p.102
  • Ex 4E Kinematics p.115-117
  • Act 12B Projectile Motion p.140-141
  • Ex 4F Projectile Motion p.119-124
  • Act 9A Vectors p.108-109
  • Ex 4A Vectors p. 90-94
  • Act 10A Forces p.117-118
  • Act 10B Forces p.123-124
  • Ex 4B Forces p.97-104
  • Act 13A p.148-149 Circular Motion
  • Ex 4H p.132-134 Circular Motion
  • Ex 2B, p.16-18, Graphing
  • Ex 2C, p.19-25, Identifying Relationships and Experimental Equations
  • Ex 2B, p.23-40, Level 3 Handout booklet on Graphing Errors
Revision for Lab assessment

Errors & Processing - Link (scroll to bottom of page)

What's the difference between accuracy 

and precision? 

(Systematic Error & Ramdom Error)





Linerising Graphs in Physics

Linerisation of Data


Uncertainties and Errors

World's Heaviest Weight - the importance of error reduction through measurement

Sunday, 5 March 2023

Week 6 Term 1 2023

 Homework

  • Act 8B Graphs of motion p.101
  • Act 8C Kinematics p.102
  • Ex 4E Kinematics p.115-117
  • Act 12B Projectile Motion p.140-141
  • Ex 4F Projectile Motion p.119-124
  • Act 9A Vectors p.108-109
  • Ex 4A Vectors p. 90-94
  • Act 10A Forces p.117-118
  • Act 10B Forces p.123-124
  • Ex 4B Forces p.97-104
  • Act 13A p.148-149 Circular Motion
  • Ex 4H p.132-134 Circular Motion

Circular Motion
  • Velocity is always at a tangent to the circle. Even if the speed remains constant, the velocity is changing because it is accelerating.

vc = 2𝝿r/T

  • Centrapetal Acceleration is always toward the centre of the circle.
  • ac = mv2/r
  • Centapetal Force is the Net Force, and is also always towards the centre of the circle.

Fc = mv2/r

Uniform Circular Motion



Circular Motion




Derivation of Centripetal Acceleration

Centrapetal vs Centrafugal


Faking Gravity

What is the Coriolis Effect?