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

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)

L2 Relationships Videos (click here)

L3 Errors Videos (click here)

Linerising Graphs in Physics

Linerisation of Data

Uncertainties and Errors

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

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

PHet Application on Circular Motion

Derivation of Centripetal Acceleration

Centrapetal vs Centrafugal

Faking Gravity

What is the Coriolis Effect?

Week 5 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

Force

Mass on a Slope

Drawing a Free Body Diagram

Net Force - PhET Application - link here

What is a Force?

What Forces are Acting on You?

Best Film on Newton's Third Law Ever

What is Gravity

The Difference Between Mass & Weight

Misconception About Falling Objects

Week 4 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

Projectile Motion

See Projectile Motion Videos at the bottom of the Mechanics Webpage - link here

PhET - Projectile Motion  - link here

Projectile Motion - Khan Academy

Horizontal & Vertical Vectors in Projectile Motion

Introduction to Projectile Motion

Vectors

A vector has a magnitude (size) and direction

Vector Addition

• Always add Head to Tail
• It does not matter which order you add vectors

Adding & Subtracting Vectors

What is a Vector?

Week 3 Term 1 2023

  Kinematics

Homework

• Act 8B Graphs of motion p.101
• Act 8C Kinematics p.102
• Ex 4E Kinematics p.115-117

Kinematics Slide Presentation - How to choose and use the correct Kinematic

Kinematic Equations

Only used when an object is accelerating

vf = vi + at	← missing d
vf2 = vi2 + 2ad	← missing t
d = vit + ½at2	← missing vf
d = (vi + vf)t/2	← missing a

Choose the kinematic equation based on:

• what quantities you are given
• what quantity is asked for
• what quantity is not involved

Acceleration and Kinematic Equations

Introduction to the Kinematic Equations

Week 7 Term 3 2022

 Homework:

• Act 5A, p,53, Pulses and Waves
• Ex 3D, p.66--67, Wave Properties
• Ex 3F, p.3F, p.73-75 Superposition

Basic Properties of Waves

waves transfer energy through a medium without transferring the medium itself

• Cycle - a basic repeating unit in a wave
• Amplitude A (m) - the distance from the middle point to the top of a crest, or bottom of a trough
• Wavelength 𝜆 (m) - the distance/length of one cycle
• Period T (s = s per cycle) - the time it takes for one cycle to pass a point
• Frequency f (Hz = cycles per second) - the number of cycles that pass in one second

T = 1/f & f = 1/T

• Wave Speed v (ms-1) the speed of a wave

v = 𝜆/T & v = f𝜆

Wave Properties

Frequency & Period

Wave Phase

Pendulum Waves

Longitudinal Waves

particle displacement in the medium is parallel to the direction of wave propagation e.g. sound waves, primary earthquake waves

Transverse Waves

particle displacement in the medium is perpendicular to the direction of wave propagation e.g. light and other electromagnetic waves, secondary earthquake waves

• Superposition of Waves: two waves traveling through each other will not change each other motion in any way, but they will add to one another when they overlap
• Constructive Interference - Reinforcement - In Phase
• Destructive Interference - Cancellation - Out of Phase

PhET Waves on a String App - link

Reflection on A String

Hard Boundary

Wave reflects on opposite side (opposite phase)

Same Amplitude, A

Same Wavelength, 𝛌

Same Wave Speed, v

Reflection on A String

Soft Boundary

Wave reflects on same side (same phase)

Same Amplitude, A

Same Wavelength, 𝛌

Same Wave Speed, v

Refraction on A String

Fast to Slow Boundary

Relation of waves to Incident Wave

Reflected Wave - same speed - same wavelength 𝛌 - opposite phase

Refracted Wave - slower speed - smaller wavelength 𝛌 - same phase

Refraction on A String

Slow to Fast Boundary

Relation of waves to Incident Wave

Reflected Wave - same speed - same wavelength 𝛌 - same phase

Refracted Wave - faster speed - larger wavelength 𝛌 - same phase