Electromagnetic Spectrum
These resources support teaching about the electromagnetic spectrum and include background information which non-specialists will find useful.
Visit the practical work page to access all resources and lists focussing on practical work in secondary science: www.nationalstemcentre.org.uk/sciencepracticals
Key Stage Four: Infrared
Herschel is perhaps most famous for his discovery of the planet Uranus in 1781, but he also discovered the existence of infrared radiation.
In this lesson, students re-create Herschel’s experiment to demonstrate infrared radiation (detailed teachers notes are provided).
You could use the film clip listed below to lead into the PowerPoint presentation which describes the use of IR in space exploration.
The electromagnetic statement cards make a great plenary. Working in pairs the students match the keywords with the correct statement. When the cards are turned over they reveal images of animals in visible light and infrared light.
As an extension, students can investigate the use of IR to measure sea temperature, and how sea temperature affects phytoplankton growth. This links well with climate change.
Infra-red: More Than Your Eyes Can See
This video makes a good introduction to practical activities investigating infrared radiation.
It looks at how infra-red cameras see the world and are used to explore space. It describes the electromagnetic spectrum and how infra-red is a measure of heat radiation. The video concludes by showing how infra-red can be used in astronomy to observe distant stars and galaxies.
Seeing Beyond the Visible
This resource describes a range of activities using silicon-based sensors (digital cameras, webcams, camera phones). The booklet looks at these sensors and imaging software and how they can be used to obtain and manipulate infrared and visible images. The activities can be used when introducing the electromagnetic spectrum or discussing colours.
Non-specialists will appreciate the accessible overview of the theory behind imaging.
Mobiles and Tissues
Microwaves are a form of electromagnetic radiation and they penetrate into human tissue. There is still a significant debate about the safety of holding even a low power microwave transmitter (like a mobile phone) next to your brain or keeping it in a trouser pocket. The possibility of damage to bodies may be particularly significant during early teenage years when there are many changes in human physiology.
In this activity, a microwave monitor is used to measure the microwave radiation from a microwave oven and a working mobile phone at a range of distances. The phone being used will need to be “locked” into 2G mode for this activity to work correctly!
The podcast makes an excellent introduction to communications technology - how mobile phones use microwave radiation, network coverage, signals and antennas.
Medical Physics in the Electromagnetic Spectrum
This is not a practical resource, but it is included here as the presentation is a fantastic way of giving context to investigating the electromagnetic spectrum and illustrating the use of the EMS in medical physics. It also shows students the wide variety of careers available in healthcare for those with physics qualifications.
Communications: Transmitting and Receiving Signals
Mobile phones, computer networks, remote controls and satellite links all involve communications technologies which make use of electromagnetic radiation as a means of carrying information.
The booklet in this resource describes how to use two sets of equipment (the SEP Optical Transmission Set and the SEP Analogue/Digital Transmission Set) to illustrate this.
The first of these uses visible light to demonstrate some basic principles of sending signals using electromagnetic radiation, such as transmission and detection, attenuation, noise and the use of optical fibres. The second set uses infrared radiation to demonstrate how carrier waves can be used for analogue and digital signals. Both sets can be used to model the way that radio waves are used to transmit information about audio signal.