UV Light
Physics: Edexcel IGCSE, topic 3.3.4
Ultraviolet Light
Ultraviolet light is between X-rays and visible light in the electromagnetic spectrum.
Uses
- Ultraviolet light is used in medical and forensic photography, air purification, disinfection and medical therapy.
- Ultraviolet light can also be used to detect fake bank notes.
Risks
- Exposure to too much ultraviolet light can cause skin burns, skin cancer and cataract formations in the eye.
Explanation
- In lamps, UV photons excite (gives energy to) atoms. The atoms then release visible light.
- In sun tanning, UV excites (gives energy to) skin cells. The skin cells then change colour.
Test yourself on UV Light
Which one of these health issues cannot be caused by exposure to too much UV light?
Why should exposure to too much ultraviolet light be avoided?