Unit 2- Waves Flashcards
Amplitude
Maximum displacement of a particle caused by wave motion
Wavelength
Distance between two adjacent points on a wave with the same phase
Period
The time taken for one whole cycle of the wave
Phase difference
How far ‘out of step’ the oscillation is at two points on the same wave
Frequency
Number of cycles of wave per unit time
Speed of a wave
Distance travelled by the wave per unit time
Intensity
Incident energy per unit area per unit time
Diffraction
Wavefronts spread out after passing through a gap or around an obstacle
Condition for significant diffraction to occur
The size of the gap or obstacle must be comparable to the wavelength of the wave
Interference
When waves superpose at a point to produce a change in the overall intensity
Principle of superposition
When 2 or more waves meet the resultant displacement is equal to the sum of the displacement of each wave
Coherent
Two waves are coherent if there is a constant phase difference between the waves
Conditions for double-slit interference to occur
Two wave sources which are coherent and of similar amplitude
Condition for constructive interference (wave sources in phase)
Path difference = whole number of half wavelengths
Condition for destructive interference (wave sources in phase)
Path difference = odd number of half wavelengths
