Physics Unit 4 - Light vs Sound Flashcards
What is light?
Type of electromagnetic wave that travels at light speed
What is light speed?
3 x 10^8
What is the EM spectrum
Continuous spectrum of electromagnetic waves/ radiation with different properties
What are the properties of EM waves
Frequent
Ionising ability
Wavelength
What waves make up the EM spectrum?
Radio waves
Microwaves
Infra red
Visible light
UV radiation
X rays
Gamma rays
Properties of EM waves?
Travel in a vacuum
Travel at light speed
Transverse waves
Can be plane polarised
They can be reflected, refracted and diffracted
They can have interference patterns
What are the properties of a sound wave?
Is it us a longitudinal wave, oscillations are parallel to direction of energy transfer, it can not travel through a vacuum.
In what material will a longitudinal wave travel quickest and why?
In dense materials sound waves can move quicker because there are more particles to bounce off.
Radio waves
Microwave
Infra red
Visible loght
UV
X-ray
Gamma ray
What is amplitude of a wave?
Maximum displacement from the mean point.
What is a wavelength
Distance between two successive identical points on a wave.
What is frequency?
The number of oscillations per unit time.
What is the displacement of wave
It is the distance any point on the wave has moved from mean or rest position.
What determines the pitch of the wave?
Frequency
What does the amplitude of the wave determine?
The volume of sound.
What is the normal human hearing range of sound waves?
20 herts
What is super position of waves?
When two waves meet travelling in opposite directions producing a resultant wave with the displacement that is the sum of the individual wave.
What is the structure of the ear?
Ear/pina/auricle
Auditory canal - carries sound vibrations
Tympanic membrane - sound waves vibrate
Malleus + incus + stapes - transmit sound wave vibrations from the eardrum to the cochlea
Cochlea - converts sound into neural signals1
What is the normal hearing range?
20 hertz - 20000 hertz
Why does long exposure to loud sounds damage your hearing?
Over work the ossicles so they become stiff
Damage the cochlea by over stimulating
Damage to the eardrum
Law of reflection
Angle of incidence = angle of reflection
What is refraction?
Refraction occurs when a wave changes direction as it passes one medium to another.
