General Principles of Radiation
Science: KS3, topic 3.3.32
Radiation
Infra-red radiation can transfer thermal (heat) energy without needing a medium. A medium is a substance to travel through. All bodies (objects) emit radiation.
Electromagnetic wave
- Infra-red radiation is a type of electromagnetic wave.
- Infra-red radiation is part of the electromagnetic spectrum.
- We cannot see infra-red radiation, but we can feel it as heat.
The Sun
- The Sun emits infra-red radiation.
- Infra-red radiation transfers thermal (heat) energy to Earth.
- Infra-red radiation does not need a medium.
- So infra-red radiation can travel through space.
Test yourself on General Principles of Radiation
What does the word 'medium' mean?
Which of the following statements are true of infra-red radiation?
Why does the Sun make us feel warm?
How is infra-red radiation detected differently from visible light?