Radiation
Physics: Edexcel IGCSE, topic 4.4.1
Radiation
Infra-red radiation can transfer thermal energy without a medium (substance to travel through).
Electromagnetic wave
- Infra-red radiation is an electromagnetic wave (it is part of the electromagnetic spectrum).
- We cannot see it but we do feel it as heat.
The Sun
- The infra-red radiation emitted by the Sun transmits thermal (heat) energy to the Earth.
- Infra-red radiation does not need a medium, so can still travel through space.
Test yourself on 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?