Non-ionising electromagnetic radiations
Lesson details
Learning outcome
I can explain the properties, uses and dangers of non–ionising electromagnetic radiation.
Key learning points
- Radio waves, microwaves, IR and visible light are non–ionising EM radiation. They can harm cells by heating.
- Radio waves are produced by oscillations of current. When absorbed, they may produce oscillations of current.
- Radio waves and microwaves are used for long distance communication, broadcasting and data transmission.
- Microwaves are absorbed by water, so can be used to cook food from within. IR radiation cooks the surface of food.
- IR is used for heating and thermal imaging. Visible light and IR are used for data transmission in optical fibres.
Keywords
Frequency - The frequency of a wave means the number of oscillations occurring per second, which is the same as the number of waves arriving per second.
Non-ionising - Radio waves, microwaves, infrared and visible light are non–ionising electromagnetic waves, as they cannot remove electrons from atoms.
Heating - Any process that transfers energy because of a temperature difference, or causes a temperature rise, can be called heating.
Oscillations - Oscillations are the vibrations of a wave about a rest position.
Antenna - An antenna is a metal structure designed to emit or absorb electromagnetic waves.
Common misconception
The majority of pupils struggle to differentiate between ionising and non–ionising radiation.
Explicitly teach that non–ionising radiation is not able to force electrons off atoms – it cannot turn atoms into ions. What it may be able to do is cause heating by increasing the movement of particles and therefore temperature of the substance.
Teacher tip
As a variation to teaching about each type of radiation, pupils could research each one for themselves. This is best done in a structured way, perhaps with an information sheet or table for each one to complete.
Content guidance
Depiction or discussion of sensitive content
Supervision
Adult supervision recommended
Licence
except where otherwise stated. See Oak's terms & conditions (Collection 2).Lesson video
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Prior knowledge starter quiz
6 Questions
Q1.Which of the following happens when a wave is transmitted by a medium?
Q2.The of a wave is the number of wavelengths per second passing a point.
Q3.Which of the following are examples of ionisation?
Q4.Which of the following types of electromagnetic radiation has the longest wavelengths?
Q5.Which of the following types of electromagnetic radiation can cause ionisation?
Q6.Why are some types of electromagnetic radiation more ionising than others?
Assessment exit quiz
6 Questions
Q1.Some types of electromagnetic radiation are non-ionising.
Which of the following statements about non-ionising radiation are correct?
Q2.Which of the following is a definition of ‘oscillations’?
Q3.Which of the following types of radiation is used to communicate between Earth and satellites?
Q4.Four types of electromagnetic radiation are: radio waves, microwaves, infrared waves, visible light.
How many of these can harm humans, if the intensity is high enough?
Q5.Lower frequency radio waves and higher frequency radio waves can both be used for long-distance communication. Which of the following describe features of lower frequency radio waves?
Q6.Sort the following steps into the correct order to describe the process of sending and receiving a radio signal.
To help you plan your 11 physics lesson on: Non-ionising electromagnetic radiations, download all teaching resources for free and adapt to suit your pupils' needs...
To help you plan your 11 physics lesson on: Non-ionising electromagnetic radiations, download all teaching resources for free and adapt to suit your pupils' needs.
The starter quiz will activate and check your pupils' prior knowledge, with versions available both with and without answers in PDF format.
We use learning cycles to break down learning into key concepts or ideas linked to the learning outcome. Each learning cycle features explanations with checks for understanding and practice tasks with feedback. All of this is found in our slide decks, ready for you to download and edit. The practice tasks are also available as printable worksheets and some lessons have additional materials with extra material you might need for teaching the lesson.
The assessment exit quiz will test your pupils' understanding of the key learning points.
Our video is a tool for planning, showing how other teachers might teach the lesson, offering helpful tips, modelled explanations and inspiration for your own delivery in the classroom. Plus, you can set it as homework or revision for pupils and keep their learning on track by sharing an online pupil version of this lesson.
Explore more key stage 4 physics lessons from the Electromagnetic waves unit, dive into the full secondary physics curriculum, or learn more about lesson planning.