P1.5 Flashcards
What is frequency?
The number of waves passing a point each second.
What is amplitude?
The maximum height of the wave measured from the middle.
What is a wavelength?
Shortest distance between two coherent points on a wave (distance from peak to peak).
What is an oscillation?
An oscillation is a vibration.
Descibe the properties of a tranverse wave.
In transverse waves, the oscillations (vibrations) are at right angles to the direction of travel and energy transfer
Describe the properties of a longitudinal wave.
In longitudinal waves, the oscillations are along the same direction as the direction of travel and energy transfer.
Describe properties of electromagnetic waves.
Electromagnetic waves carry transverse vibrations in electrical and magnetic fields, not vibrating particles.
Electromagnetic waves do not need matter to travel through - they can travel through empty space (a vacuum). They travel at the speed of light.
What are the waves in the electromagnetic spectrum?
Radio waves, microwaves, infrared radiation, visible light, ultraviolet, x-rays, gamma rays.
Give an example of a radio wave.
Radio.
Give an example of a microwave.
Microwave.
Give an example of an infrared wave.
Remote control.
Give an example of visble light.
Seeing things.
Give an example of an ultraviolet wave.
Security pen.
Give an example of an xray wave.
X-ray.
Give an example of a gamma ray.
Used to kill cancer cells.
What is the law of reflection?
Angle of incidence = Angle of reflection
What is diffraction?
It is when the waves spread out to some extent into the area beyond the gap.
What is the dopler effect?
The apparent change in the frequency of a wave caused by the relative motion of the source of the wave to the observer.
What is red shift?
When an object away from us appears red but an oject moving towards us appears blue. it happens when light or other elctromagneits radiation is increased or shifted at the red end of the spectrum.
What is the big bang theory?
The universe had a definite start from a very small dense point. It is constantly changing.
Give a use of an electromagnetic wave in communication.
Microwave radiation can also be used to transmit signals such as mobile phone calls or radio waves are used to transmit television and radio programmes. Television uses higher frequencies than radio.
What are the properties of sound waves?
Sound waves are longitudinal waves. Their vibrations occur in the same direction as the direction of travel. Sound waves can only travel through a solid, liquid or gas.
