Wave Motion Flashcards
What are waves?
Waves are a means of transferring energy from one place to another
What are the two types of wave (medium)?
Mechanical and electromagnetic
Explain mechanical waves.
Waves that require a medium to travel through and physically disrupt that medium. Eg water waves, slinky waves and sound waves
Explain electromagnetic waves.
Waves that do not require a medium to travel through and cause electric and magnetic disruption. Eg visible light, X-rays and TV/radio waves
What are travelling waves?
Travelling waves carry energy through a medium without any overall movement of the medium
What are the two types of waves (vibration)?
Longitudinal and transverse waves
Explain longitudinal waves.
The direction of vibration of longitudinal waves is parallel to the direction in which the wave is travelling. When the wave squashes together, it’s called compression, and when it stretches out, it’s called rarefraction. Eg sound waves
Explain transverse waves.
The direction of vibration of transverse waves is perpendicular to the direction in which the wave travelling. All electromagnetic waves are transverse. Eg visible light and radio
How would you demonstrate the wave types?
By using a slinky
What is wavelength?
It is the length of a complete cycle. The symbol is λ and is measured in meters
What is amplitute?
It is the maximum displacement from the mean position. It is measured in meters
What is frequency?
The number of vibrations that occur per second. The symbol is f and is measured in Hertz (Hz)
What is speed?
It is the speed at which the wave propagates through space or medium. The symbol is c and is measured in meters per second (m/s)
What is period?
The time taken for one complete cycle to occur. The symbol is T, it is measured in seconds (s) and is the reciprocal of frequency; (T=1/f)
What are the wave phenomena?
-Reflection
-Refraction
-Diffraction
-Interference
-Polarisation
What is reflection?
The bouncing of a wave off an object.
What is refraction?
The bending of a wave as it enters a different medium and changes speed
What is diffraction?
The spreading out of a wave as it moves through a gap or around an obstacle
What is interference?
The combining of waves to form a resultant amplitude made up of each wave’s individual amplitude
What is constructive interference?
When waves combine to form an amplitude greater than each individual wave’s amplitude
What is destructive interference?
When waves combine to form an amplitude smaller than each individual wave’s amplitude
What are coherent waves?
Waves that are in step or a fixed amount out of step
An interference pattern will be produced when…
Coherent waves meet
What is polarisation?
The confining of a wave to a particular plane. This applies to transverse waves only
