Page 141 - Knowledge Organiser Yr8 24-25

Knowledge Base: Science 8.7 Electromagnetic Waves Year 8
8. Electromagnetic Waves
8.1 Light is a form of what type of wave?
An electromagnetic wave.
8.2
What is the order of the electromagnetic spectrum from the wave with the longest wavelength to the shortest?
8.3
What properties do all electromagnetic waves have in common?
All of the electromagnetic waves can be reflected and refracted, they all travel at the speed of light and they can all travel through a vacuum.
Knowledge builder: Using electromagnetic waves
9.1 Describe the use and hazards of the electromagnetic waves.
EM Wave
Use
Hazards
radio waves microwaves infrared waves visible light ultraviolet X-rays
gamma waves
Broadcasting and Communications.
Cooking food.
Heaters and night-vision equipment.
Vision, photography, optical fibres.
Fluorescent lamps to check bank notes.
Medical equipment to see bones.
Sterilise food/ medical equipment and treating cancer.
Very small rise in temperature. Usually not harmful to humans.
Can cause internal heating of body tissues.
Burns due to heating.
Intense visible light (laser) can damage the retina at the back of the eye.
Can damage skin cells and lead to skin cancer, premature aging and damage to your eyes. Damage to cells in the body. DNA can be damaged and can lead to cancer.
Damage cells inside the body. DNA can be damaged and can lead to cell death and cancer.
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