3.16 Plane mirrors

For plane mirrors, the image would be.....

• The same size as the object.
• The same distance as the object from the mirror.
• Virtual (not real).
• Upright.
• Laterally inverted.

3.15 Light waves are transverse waves which can be reflected, refracted and diffracted

Angle of incidence i	Angle of reflection r
10o	10o
20o	20o
30o	30o
40o	40o
50o	50o

Formula: i = r

3.13 Effects of excessive exposure of the human body to electromagnetic waves

• Microwaves- Internal heating of body tissue.
• Infrared- Skin burns.
• Ultraviolet- Damage to surface cells and blindness.
• Gamma rays- Cancer, mutation.

3.12 Electromagnetic Uses

• Radio waves- Broadcasting and communications.
• Microwaves- Cooking and satellite transmission.
• Infrared- Heaters and nigh vision equipment.
• Visible light- Optical fibres and photography.
• Ultraviolet- Fluorescent lamps.
• X-rays- Observing the internal structure of objects and materials and medicals applications.
• Gamma rays- Sterilising food and medical equipment.