Lesson Plan: P2.4.06

Hamble Lesson Observation Plan
Learning About
What are the uses and dangers of the electromagnetic spectrum?
Keywords:
  • Transmit: move from one place to another (1)
  • Absorb: when a wave transfers its energy to the material it penetrates. (1)
  • Refract: when waves change speed when they move from one medium to another of different density (1)
  • Reflect: when waves bounce back off a reflective surface (1)
  • Wavelength: family of waves with similar properties (1)
  • Electromagnetic (1)
  • Mutations: random changes to DNA (1)
  • Gamma: the most ionising electromagnetic wave (1)
  • Circuits: An electric circuit is a path in which electrons from a voltage or current source flow (1)
  • Electrical: energy transfer (1)
  • Waves: how energy is transferred but matter is not (1)
  • Ionising: radiation that carries enough energy to remove electrons from atoms (1)
  • X-ray: a type of ionising radiation (1)
  • Oscillation: one complete cycle of a wave (1)
Memory Anchor:
Method Precise Learning Objective Linked Question / Activity
(Designed for maximum working out)		 Stepping Stones Pitstop Check
(Thinking Map)
(HT only) Radio waves can be produced by oscillations in electrical circuits. (HT only) How are radio waves produced?
Changes in atoms and the nuclei of atoms can result in electromagnetic waves being generated or absorbed over a wide frequency range. How can electromagnetic waves be generated?
Ultraviolet waves, X-rays and gamma rays can have hazardous effects on human body tissue. What types of waves are hazardous on human body tissue.
Gamma rays originate from changes in the nucleus of an atom. How are gamma rays generated?
Ultraviolet waves can cause skin to age prematurely and increase the risk of skin cancer. What effects can Ultraviolet waves cause to the skin?

EW: Why is it important to wear sun cream that has a high UV rating?
Going from long to short wavelength (or from low to high frequency) the groups are: radio, microwave, infrared, visible light (red to violet), ultraviolet, X-rays and gamma rays.

*Duplicated from lesson 5* combined tier to teach in lesson 6. Higher tier covered in lesson 5
Students should be able to give examples that illustrate the transfer of energy by electromagnetic waves. What are three ways that show energy is transferred by electromagnetic waves?

For each part of the EM wave consider the applications of each one and then identify the energy transformations that are occurring
The effects depend on the type of radiation and the size of the dose. What effects the outcome of being exposed to radiation?
Students should be able to draw conclusions from given data about the risks and consequences of exposure to radiation. What are the risks and consequences of exposure to radiation?
X-rays and gamma rays are ionising radiation that can cause the mutation of genes and cancer. What type of electromagnetic waves are ionising?

GF: Describe the changes to DNA that exposure to radiation can occur. What effects can this have on the cell and the rest of the body?
Electromagnetic waves have many practical applications. For example: - radio waves - television and radio - microwaves - satellite communications, cooking food - infrared - electrical heaters, cooking food, infrared cameras - visible light - fibre optic communications - ultraviolet - energy efficient lamps, sun tanning - X-rays and gamma rays - medical imaging and treatments.

*Duplicated for combined only in this lesson* Higher tier groups to teach this in lesson 5. Watch the video on how UV waves are used to produce images of unborn babies. Create a thinking map to help you answer. EW: How are EM waves used in medical imaging? https://www.youtube.com/watch?v=GvbXHoiQHbI
(HT only) When radio waves are absorbed they may create an alternating current with the same frequency as the radio wave itself, so radio waves can themselves induce oscillations in an electrical circuit. (HT only) What type of current is produced when radiowaves are absorbed?

Use the phet animation to show the electromagnetic fields from radio waves. https://phet.colorado.edu/en/simulation/legacy/radio-waves
Different substances may absorb, transmit, refract or reflect electromagnetic waves in ways that vary with wavelength. (HT only) How can the wavelength of electromagnetic waves be varied?
Radiation dose (in sieverts) is a measure of the risk of harm resulting from an exposure of the body to the radiation. What units is radiation measured in?
1000 millisieverts (mSv) = 1 sievert (Sv) Students will not be required to recall the unit of radiation dose. How many millisieverts are there in 1 sievert?
(HT only) Students should be able to give brief explanations why each type of electromagnetic wave is suitable for the practical application. (HT only) Why is each type of electromagnetic wave suitable for practical application?

Use an image of the EM waves to compare the frequency and wavelength. Demonstrate an optical fibre showing total internal reflection. Demonstrate a use of UV by shining a UV light onto a bank note, through tonic water or writing a message using a security marker and then holding a UV light over the message.
Links To the Big Ideas
ForcesParticlesEnergyCells