Week 2 Term 1 2024

 

Homework:

• Activity 11A, p.188-189 Waves & Photons
• Activity 11B, p.192 Photoelectric Effect
• Exercise 5B, p.205-208 Photoelectric Effect
• Ex 5C, p.212-215 Photoelectric Effect
• Act 11C, p.183 Atomic Line Spectra
• Act 11D, p.188-189 Bohr Model of Hydrogen Atom
• Ex 5D, p.221-222 Atomic Models
• Ex 5E, p.228-230 Atomic Line Spectra

Photoelectric Effect

Photoelectric Effect A-Level Physics

Hertz and Lenards Observation of Photoelectric Effect

Photoelectric Effect

The concept of the Photoelectric Effect was introduced and how light modeled as a particle can explain this, while light modeled as a wave cannot.

The above video explains the Photoelectric Effect using a PhET application which I encourage you to use and experiment with.

This can be found at:

 https://phet.colorado.edu/en/simulation/photoelectric

Planck's Constant h = 6.63 x 10^-34 Js

Energy of a Photon E = hf

Threshold Frequency f_{o ,} the frequency of incident photons that have an energy equal to the work function of the metal

Work Function φ = energy required to free an electron from a specific metal (J)

Maximum Kinetic Energy, E_k,  of a freed electron by an incident photon:

E_k = hf - φ

Electron Volts to Joules Conversion

How Quantum Mechanics Saved Physics From Ovens

Planck's Constant - Sixty Symbols

How Quantum Mechanics Saved Physics From Ovens

Planck's Constant - Sixty Symbols

Bohr Model of the Hydrogen Atom - applet link

Atomic Line Spectra

Hydrogen Emission and Absorption Spectra for the visible Balmer Series

Atomic Line Spectra for Hydrogen

Emission & Absorption Lines for Hydrogen

Emission Lines for Hydrogen

Bohr Model of the Hydrogen Atom

 Bohr Model of the atom and Atomic Emission Spectra

Line Spectra & the Bohr Model

Emission and Absorption Line Spectra

Energy Levels

Bohr Model of the Hydrogen Atom

Atomic Spectroscopy Explained

Fine Structure Constant 1/137

Term 1 Week 2 2022

 Homework:

• Activity 11A, p.176 Waves & Photons
• Activity 11B, p.179 Photoelectric Effect
• Exercise 5B, p.205-208 Photoelectric Effect

Photoelectric Effect

Photoelectric Effect A-Level Physics

Hertz and Lenards Observation of Photoelectric Effect

Term 1 Week 5 2018

Homework:

• Ex 11C Spectral Lines - ESA Text (last week)
• Ex 11D Atomic Energy Levels - ESA Text (last week)
• Ex 12 A E = mc2 - ESA Text
• Ex 12 B Nuclear Reactions ESA Text

Electron Volts to Joules Conversion

Mass? Energy? What's The Difference?!

Mass Defecit & Binding Energy

Where does the Sun get its Energy?

Binding Energy per Nucleon

Mass per Nucleon

Mass deficit and binding energy in FUSION

Mass deficit and binding energy in FISSION

Einstein's Proof of E=mc²

Why is Light the Fastest Thing?

Term 1 Week 5

Homework: 

Ex 10, p.189-198 Modern Physics - this will be assessed on Friday 4th March and covered the Modern Physics Topic Phy 3.5 AS 91525. This topic will be assessed in Week 8.

Electron Volts:

Some people have been getting confused by electron volts eV.
An electron volt is the amount of energy needed to move an electron through one volt of electrical potential.
Recall electrical potential energy:

E_p = qV

q: Charge in Coulombs (C)

V: Voltage in Volts (V)

The charge of one electron e = 1.60 x 10^-19 C

So the energy reqired to move one electron through one volt is:

1.60 x 10^-19 C x 1 V = 1.60 x 10^-19 J

so                       1eV = 1.60 x 10^-19 J

Using eV for energy is just a way of showing the small energies involved in one or few particle reactions. 

Always use energy in Joules when calculating. This is the S.I. unit for energy.

Converting: