Sunday, 22 July 2018

Term 2 Week 10 2018

Homework

Ex 3D, p.66--67, Wave Properties
Ex 3E, p.69-70, Diffration
Ex 3F, p.73-75 Superposition
Ex 3G, p.76-78 Two Point Source Interference
Ex 3H, p.81-83 Waves on a String
Ex 3I, p.85-87 Wave Refraction on a String

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

Diffraction

The Bending of Waves Around Corners

Larger Wavelength, 𝛌 - greater the angle of diffraction

Shorter Wavelength, 𝛌 - smaller the angle of diffraction

Also the smaller the gap the greater the angle of diffraction

Diffraction

Diffraction of Water Waves in a Ripple Tank

Two Point Source Interference

Two Point Source Interference

Double Slit Experiment

PhET Sound Wave Interference - link

PhET Wave Interference - link

Cymatics

Monday, 25 June 2018

Term 2 Week 9 2018

Homework

Ex 3D, p.66--67, Wave Properties
Ex 3E, p.69-70, Diffration
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
Deconstructive Interference - Cancellation - Out of Phase

Term 2 Week 8 2018

Homework

Ex 5A, p. 151-155, Models of the Atom
Ex 5B, p. 160-171, Radioactivity
Ex 5C, p. 175-182, Nuclear Reactions

Revision for the Atomic & Nuclear Assessment next week

Atomic and Nuclear Pre-Aligned Exams AS 90253

(Scroll to the bottom of this page - link)

The pre-aligned Standard Covering:

Historical models of the Atom;
Half-Life;
but not Nuclear Reactions

Monday, 11 June 2018

Term 2 Week 7 2018

Homework

Ex 5A, p. 151-155, Models of the Atom
Ex 5B, p. 160-171, Radioactivity
Ex 5C, p. 175-182, Nuclear Reactions

Nuclear Reactions:

Conservation of Atomic Number

Conservation of Nucleon Number

Conservation of Mass-Energy E = Δmc2

E = Δmc2

Nuclear Fusion in the Sun

Binding Energy comes from the change in mass from individual nucleons to being combined into a nucleus. This is energy lost by the nucleons joined together in a nucleus and must be returned in order to separate the nucleons

E = Δmc2

Mass Energy Equivalence

Nuclear Reactions

Fission Fusion and Radioactive Decay

Fission & Fusion

Term 2 Week 6 2018

Homework:

Ex 5A, p.151-155, Models of the Atom
Ex 5B, p. 160-171, Half-Life

Rutherford'd Den and Canterbury University Field Trip

Monday, 28 May 2018

Term 2 Week 5 2018

Homework:

Ex 4G, p. 125-130, Torque, Static Moments
Ex 5A, p.151-155, Models of the Atom
Ex 5B, p. 160-171, Half-Life

Alpha, Beta, Gamma Ionising Radiation

Ionising Radiation is radiation that will give a charge to matter. This includes EM radiation (photons) that have enough energy to ionise - e.g. X-Rays and 𝜸 - Rays. This also includes charged particles such as α and 𝞫 particles.