Unit 2 definitions Flashcards
Amplitude:
the maximum displacement from the mean position
Frequency:
the number of complete oscillations per second
Period:
the time taken for one complete oscillation
Wavelength:
the distance between the same point on two successive waves
Longitudinal waves:
direction of oscillation is parallel to the direction of propagation. Wave travels with series compressions and rarefactions.
Jan 2010: Describe how sound waves travel through air (3)
Sound waves are longitudinal (1)
Air molecules vibrate (1)
Parallel to the direction of travel of the wave (1)
In a series of compressions and rarefactions (1)
Transverse waves:
direction of oscillation is perpendicular to the direction of propagation with peaks and troughs.
Wavefront:
a line representing all points of a wave that are in phase, i.e. peaks of a wave as viewed from above.
Coherent:
Waves of constant phase relationship (Jan 2010)
Path Difference:
the difference in distance from each source to a particular point
Superposition:
when two or more waves of the same type meet at a point the resultant displacement of the oscillations will be the vector sum of the individual displacements
Phase:
Phase:
Standing Wave:
no net transfer of energy or pattern of nodes and antinodes or points of maximum displacement and zero displacement (Jan 2010)
June 2009: Explain why the amplitude of sound varies for a microphone being moved between a speaker and a screen (4)
Interference pattern produced / superposition occurs / standing wave formed (1)
Maxima related to constructive interference / antinode and/or minima related to destructive interference/node (1)
Maxima/antinode formed where the waves are in phase / path difference nλ (1)
Minima/node formed where the waves are in antiphase/path difference = (n+1/2)λ (1)
Progressive Wave:
a wave which transfers energy but not matter