- Special cameras can 'see' animals and people in the dark, detecting infrared radiation. Every object can emit-give out-infrared radiation in heat.
- The hotter an item/object is, the more infrared radiation it emits.
- A thermometer can be used to detect infrared radiation:
- Using a glass prism, a beam of light should be shone through it.
- The white light from the beam splits into the colours of the spectrum- Red, orange, yellow, green, light blue, dark blue, violet.
- On the electromagnetic spectrum, infrared radiation comes just before visible light-before the red side of the colour spectrum, invisible to the eye.
- Therefore, as the spectrum is shone out from the screen, placing a thermometer next to the red light increases the temperature.
- Electromagnetic spectrum-electrical and magnetic waves that travel through space:
- Radio waves