Physics Waves Flashcards
Define frequency.
The number of complete oscillations per second.
Define wavelength.
The distance from the peak of one crest to the peak of an adjacent crest.
Define amplitude.
The distance from the equilibrium position to the peak of a wave.
Define a longitudinal wave.
A wave where the direction of oscillation is parallel to the direction of energy transfer.
Define a transverse wave.
A wave where the direction of oscillation is perpendicular to the direction of energy transfer.
Define the time period.
The time taken for one complete oscillation.
What two things do waves transfer?
Energy and information.
Give an example of a transverse wave.
Light
Give an example of a longitudinal wave.
Sound
When a sound wave has a large frequency, how does it sound?
High pitched
When a sound wave has a large amplitude, how does it sound?
Loud
When a sound wave has a low frequency, how does it sound?
Low pitched
When a sound wave has a low amplitude, how does it sound?
Quiet
What is the equation for the speed of a wave?
wave speed = frequency x wavelength
What is the equation for the frequency in terms of time period?
Frequency = 1 / Time period
What is the equation for calculating the frequency of a wave?
Frequency = number of waves / time taken for those waves to pass a point
What is the range of human hearing?
20 Hz -> 20000 Hz
What is ultrasound?
Sound waves above 20000 Hz
What is the order of the EM spectrum with increasing frequency?
Radio, Micro, IR, Light, UV, X, Gamma
What is the order of the EM spectrum with increasing wavelength?
Gamma, X, UV, Light, IR, Micro, Radio
What is the order of the colours in increasing frequency?
Red Orange Yellow Green Blue Indigo Violet
What is the order of the colours in increasing wavelength?
Violet Indigo Blue Green Yellow Orange Red
What is an application of radio waves?
Broadcast communications
What is an application of microwaves?
Satellite communication
What two regions of the EM spectrum can be used for cooking?
IR, Micro
What is a danger of microwaves?
Internal tissue heating
What is an application of Infrared?
Television remotes
What is a danger of infrared?
Skin burns
What is an application of visible light?
Photography
What is a danger of visible light?
Blindness
What is an application of UV?
Tanning salons
What are the dangers of UV?
Aging sunBurns and Cancer
How can you protect against UV?
Sun tan lotion
What is a medical application of X rays?
Shadowy images of bones for medical purposes.
What is a danger of X rays?
Cell mutations, Cancer
What is a non-medical application of X rays?
X ray crysallography
What is a medical application of gamma rays?
Radiotherapy.
What is a non-medical application of gamma rays?
Detecting cracks in metals.
What is a danger of gamma rays?
Cancer, Cell mutation
What is true of EM waves that is not true for other waves?
All can travel in a vacuum. All travel at the speed of light in a vacuum.
What is the equation for refractive index of a material?
n = sin (i) / sin (r)
What is the equation to calculate the critical angle?
