3. Waves Flashcards
What is the difference between longitudinal and transverse waves?
Transverse - vibrations are perpendicular to the direction of the wave’s energy
Longitudinal -vibrations are parallel to the direction of the wave’s energy
What is the amplitude of a wave?
The maximum movement of particles from their resting position
What do waves do?
Waves transfer energy and information without transferring matter
What is the relationship between the speed, frequency and wavelength of a wave?
Wave speed = frequency x wavelength
What is refraction?
The change in direction of a wave due to a change in speed as it passes from one medium to another
What is reflection?
When waves bounce off when they hit an obstacle
What is the law of reflection?
Angle of incidence = angle of reflection
What is the order of the electromagnetic spectrum, longest to shortest wavelength?
Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma rays
Which colour has the longest wavelength?
Red
What are the uses of radio waves?
Broadcasting and communications
What are the uses of microwaves?
Cooking and satellite transmissions
What are the uses of infrared?
Heaters and night vision equipment
What are the uses of visible light?
Optical fibres and photography
What are the uses of ultraviolet?
Fluorescent lamps
What are the uses of x-rays?
Observing the internal structure of objects and materials
What are gamma rays used for?
Sterilising food and medical equipment
What are the dangers of microwaves?
Internal heating of body tissue
What are the dangers of infrared?
Skin burns
What are the dangers of ultraviolet?
Damage to surface cells and blindness
What are the dangers of gamma rays?
Cancer, cell mutation
What type of waves are light waves?
Transverse waves
What is the relationship between refractive index, angle of incidence and angle of refraction?
n = sin i / sin r
What type of wave are sound waves?
Longitudinal waves
