# Physics

Physics is an attempt conceptually to grasp reality as something that is considered to be independent of its being observed.

## Overview

## Grade 11

#### Semester One

### Thermal, Nuclear and Electrical Physics

*Does a coffee cup or a swimming pool have more energy?*

Energy, energy, energy! The course content in this semester is all about energy. Students will learn about some of its different forms, namely thermal, nuclear and electrical energy. They will describe, explain and predict energy transfers and transformations. An understanding of how energy is changed in heating processes, nuclear reactions and electricity is essential to appreciate how our global energy needs are met. Students will learn about (1) thermal energy and heating, (2) radioactivity and how nuclear reactions convert mass into energy, and (3) design of electrical circuits to show movement of electrical charge.

More specifically, students will:

**Heating processes**

- describe the kinetic particle model of matter
- distinguish between thermal energy, temperature, kinetic energy, heat and internal energy
- explain heat transfer in conduction, convection and radiation
- convert temperature between Celsius and Kelvin
- collect heat data in correct SI units
- explain that temperature change is due to energy change in a system
- solve problems using specific heat capacity
- solve problems using specific latent heat
- explain temperature in phase changes
- solve problems using thermal equilibrium
- explain relationship between thermal energy and mechanical work
- calculate the efficiency of heat transfers

**Ionising radiation and nuclear reactions**

- describe the nuclear model of the atom
- define the strong nuclear force
- explain the stability of a nuclide
- explain natural radioactive decay
- define alpha radiation, beta positive radiation, beta negative radiation and gamma radiation
- describe penetrating ability, charge, mass and ionisation ability of these types of radiation
- balance nuclear equations
- use decay equations
- solve radioactive half-life decay problems
- distinguish between artificial transmutations and natural radioactive decay
- explain a neutron-induced nuclear fission reaction
- define nuclear fission, nuclear fusion, mass defect and binding energy
- solve problems using Einstein’s mass–energy equivalence relationship

**Electrical circuits**

- recall law of conservation of electric charge
- solve problems using electric current and electric charge
- compare and contrast ohmic and non-ohmic resistors
- solve problems using Ohm’s Law
- solve problems involving electrical potential difference, electric current, resistance and power
- recognise series and parallel connections of components in electrical circuits
- design simple series, parallel and series/parallel circuits

#### Semester Two

### Linear Motion and Waves

*How did the slow-moving tortoise beat the faster hare?*

Displacement, velocity, time, force, momentum, constructive interference, destructive interference, diffraction — these are all terms students will come across in this semester. They will develop an understanding of how natural phenomena can be described, explained and predicted by linear motion and wave models.

More specifically, students will:

**Linear Motion and Force**

- categorise physical quantities like velocity and speed as vector or scalar
- calculate resultant vectors through the addition and subtraction of two vectors in one dimension
- compare instantaneous and average velocity
- interpret linear motion graphs
- calculate intercepts and gradients of displacement–time and velocity–time graphs
- calculate areas under velocity– time, acceleration–time and force-time graphs
- solve problems using equations of uniformly accelerated motion in one dimension
- define Newton’s three laws of motion
- identify forces acting on an object and construct free-body diagrams
- determine the resultant force acting on an object in one dimension
- solve problems using each of Newton’s three laws of motion
- define the terms momentum and impulse
- solve problems using momentum, impulse, the conservation of momentum and collisions in one dimension
- define the terms mechanical work, kinetic energy and gravitational potential energy
- calculate work done by a force
- solve problems using kinetic energy and gravitational potential energy
- interpret the area under a force–displacement graph
- interpret meaning from an energy–time graph
- define the terms elastic collision and inelastic collision
- solve problems involving elastic collisions and inelastic collisions

**Waves**

- define the terms mechanical wave, transverse wave and longitudinal wave
- indicate whether sound, seismic waves and vibrations of stringed instruments are transverse or longitudinal waves
- define compression, rarefaction, crest, trough, displacement, amplitude, period, frequency, wavelength and velocity
- identify graphical and visual representations of a wave
- calculate the amplitude, period, frequency and wavelength from graphs of transverse and longitudinal waves
- solve problems involving the wavelength, frequency, period and velocity of a wave
- define the terms reflection, refraction, diffraction and superposition
- explain phenomena related to reflection and refraction using the wave model of light
- apply the principle of superposition
- explain constructive interference, destructive interference, nodes, antinodes and the formation of standing waves
- solve problems of standing wave formation in pipes open at both ends, closed at one end, and on stretched strings
- define the concept of resonance in a mechanical system
- define the concept of natural frequency
- identify that energy is transferred efficiently in resonating systems
- explain reflection, refraction, total internal reflection, dispersion, diffraction and interference using the wave model of light
- describe polarisation using a transverse wave model
- use ray diagrams to demonstrate reflection and refraction of light
- solve problems involving the reflection of light on plane mirrors and the refraction of light at a boundary
- define Snell’s Law
- solve problems using the proportional relationship between intensity of light and the inverse-square of the distance from the source

## Grade 12

#### Semester One

### Gravity and Electromagnetism

*How can you travel at a constant speed yet be accelerating?*

Physics truly can change the world. The development of electrical power generation, artificial satellites and modern communication systems are all underpinned by an understanding of field theories that students will uncover in this semester. Students will analyse the motion of projectiles and satellites, and the motion of objects on inclined planes. Students will examine Newton’s laws of motion, the gravitational field model and the production of electromagnetic waves.

**Gravity and Motion**

- solve vector problems by resolving vectors into components
- apply vector analysis to projectile motion
- solve problems involving force due to gravity (weight) and mass
- represent the forces acting on an object on an inclined plane
- calculate the net force acting on an object on an inclined plane
- describe uniform circular motion
- define average speed and period
- solve problems involving average speed of objects undergoing uniform circular motion
- define centripetal acceleration and centripetal force
- calculate forces acting on objects in uniform circular motion
- explain Newton’s Law of Universal Gravitation
- determine the magnitude of the gravitational force between two masses
- define gravitational fields
- calculate the gravitational field strength
- define Kepler’s laws of planetary motion
- solve problems using Kepler’s third law
- derive Kepler’s third law from the relationship between Newton’s Law of Universal Gravitation and uniform circular motion

**Electromagnetism**

- solve problems involving Coulomb’s Law
- define electric fields, electric field strength and electrical potential energy
- solve problems involving electric field strength and work done when an electric charge is moved in an electric field
- define ‘magnetic field’
- represent magnetic field lines
- determine the magnitude and direction of a magnetic field around electric current-carrying wires and inside solenoids
- solve problems involving the magnetic force on an electric current-carrying wire and moving charge in a magnetic field
- define magnetic flux, magnetic flux density, electromagnetic induction, electromotive force, Faraday’s Law and Lenz’s Law
- calculate magnetic flux in an electric current-carrying loop
- describe the process of inducing an EMF across a moving conductor in a magnetic field
- solve Faraday’s Law and Lenz’s Law problems
- explain how transformers work in terms of Faraday’s Law and electromagnetic induction
- explain electromagnetic radiation in terms of electric fields and magnetic fields

**Assessment**

- Exam – 10%
- Extended Experimental Investigation – 20%
- Exam – 50%

#### Semester Two

### Special Relativity and Quantum Theory

*How can light be both a particle and a wave?*

Our understanding of the physical world evolves over time. When physicists find evidence that conflicts with our existing theories, they postulate new theories to accomodate the findings. In this unit, students will discover how observations of relative motion, light and matter cannot be explained by classical physics theories. Students will investigate the special theory of relativity and the quantum theory of light and matter. The development of quantum theory and the theory of relativity fundamentally changed our understanding of how nature operates and led to the development of a wide range of new technologies, including information storage and processing. Students will look into GPS navigation, lasers, modern electric lighting, medical imaging, quantum computers, particle accelerators, particle physics, and the Big Bang theory.

**Special Relativity **

- define frame of reference and inertial frame of reference
- define special relativity
- explain the concept of simultaneity
- explain time dilation and length contraction in regard to the constant speed of light in a vacuum
- define time dilation, proper time interval, relativistic time interval, length contraction, proper length, relativistic length, rest mass and relativistic momentum
- solve problems involving time dilations, length contraction and relativistic momentum
- explain the mass–energy equivalence relationship
- explain why no object can travel at the speed of light in a vacuum
- explain paradoxical scenarios such as the twins’ paradox, flashlights on a train and the ladder in the barn paradox

**Quantum Theory**

- explain how Young’s double slit experiment supports the wave model of light
- describe light as an electromagnetic wave
- explain black-body radiation
- solve problems using the energy, frequency and wavelength of a photon
- describe the photoelectric effect in terms of the photon
- define threshold frequency, Planck’s constant and work function
- show that photons exhibit the characteristics of both waves and particles
- describe the Rutherford and Bohr model of the atom
- explain light quanta and atomic energy states
- describe wave–particle duality of light

**Standard Model**

- define elementary particle, antiparticle, baryon and meson
- recall the six types of quarks, the six types of leptons and the four gauge bosons
- describe the strong nuclear, weak nuclear and electromagnetic forces in terms of the gauge bosons
- contrast the fundamental forces experienced by quarks and leptons
- explain electron-electron, electron-positron and neutron decay interactions of particles using Feynman diagrams
- describe the significance of symmetry in particle interactions

**Assessment**

- Research investigation – 20%
- Exam – 50%

## Assessment

The key to high grades in any subject is strict adherence to the task and its criteria. To achieve an A+ level result for assessment in Physics, students must:

- accurately describe and explain a variety of concepts, theories, models and systems, and their limitations
- give clear and detailed accounts of a variety of concepts, theories, models and systems by making relationships, reasons or causes evident
- accurately apply understanding of scientific concepts, theories, models and systems within their limitations to explain a variety of phenomena, and predict outcome/s, behaviours and implications
- accurately use representations of scientific relationships and data to determine a variety of unknown scientific quantities
- perceptively recognise the limitations of models and theories when discussing results
- analyse evidence systematically and effectively by identifying the essential elements, features or components of qualitative data
- use relevant mathematical processes to appropriately identify trends, patterns, relationships, limitations and uncertainty in quantitative data
- interpret evidence insightfully by using their knowledge and understanding to draw justified conclusions based on their thorough analysis of evidence and established criteria
- investigate phenomena by carrying out effective experiments and research investigations
- efficiently collect, collate and process relevant evidence
- critically evaluate processes, claims and conclusions by insightfully scrutinising evidence, extrapolating credible findings, and discussing the reliability and validity of experiments
- communicate effectively by using scientific representations and language accurately and concisely within appropriate genres