Module 4 - Basic Waves Properties Flashcards
Define ‘Progressive Wave’
A Wave that transfers energy through its surroundings by means of oscillations/vibrations.
Name the 2 main types of Progressive Waves; and types of those waves.
Transverse (Such as the EM Waves and Water Waves)
Longitudinal (Such as Sound, Ultrasound, and S-Waves.)
Describe the movement of particles and it’s relationship to the direction of travel of a Transverse Wave.
Particles in a Transverse Wave oscillate perpendicular (90°) to the direction of wave travel.
Describe the movement of particles and it’s relationship to the direction of travel of a Longitudinal Wave.
On a Longitudinal Wave, particles displaced (bounced of their neighbours) in a sense that it oscillates parallel to the direction of energy transfer. (wave travel)
What is Rarefaction, and what type of wave has it?
Rarefaction is a region of a Longitudinal Wave with lower pressure.
What is Compression, and what type of wave has it?
Compression is a region of a Longitudinal Wave with higher pressure.
What is ‘wavelength’ and how is it represented?
Wavelength is the minimum distance between 2 points in phase on adjacent waves; represented by λ (lambda).
What is ‘amplitude’ and how is it represented?
Amplitude: the maximum displacement from a particle’s equilibrium position;
What is ‘displacement’ and how is it represented?
Displacement: The distance from the equilibrium position in a particular direction.
It’s a Vector, so it can be positive or negative.
Represented as y(t), where t is time and y is the displacement at that time.
What are ‘peaks’ and troughs?’
Peaks and Troughs are the maximum and minimum displacements a Transverse wave’s particles can oscillate to respectively.
What is a ‘time period’, what is it’s symbol, and what are its units?
Time Period is the time taken for one complete oscillation or wavelength.
It’s symbol is T, and it’s units are in seconds.
What is ‘frequency’, what is it’s symbol, and what are its units?
Frequency is the number of wavelengths per unit of time.
It’s symbol is ƒ, and it’s units in Hz.)
What is the formula for a Time Period?
T=1/ƒ
What is the formula for Frequency?
ƒ=1/T
What does the x-axis represent on a Oscilloscope?
Time (Modified with the Time Base)
What does the y-axis represent on a Oscilloscope?
Voltage, modified with the Voltage Scale
How do you measure the Amplitude of a wave on an Oscilloscope?
Multiply the smallest division (squares) by the Voltage Scale (Voltage value per square).
Derived Units: V cm^-1 (Volts per centimetre)
How do you measure the Time Period (T) on an Oscilloscope?
Multiply the number of squares of one wavelength by the Time Base.
Units will be in whatever fraction of a second the Time Base is.
How do you calculate Frequency using an Oscilloscope?
1/Time Period
(Where the units for Time Period are first converted to seconds.)
Derived units are 1/s, A.K.A. Hertz (Hz)
What does CRO stand for?
Cathode Ray Oscilloscope
What is the formula for wave speed?
‘The Wave Equation’
v = ƒλ
Derive the formula for wave speed from s = d/t
- s = d/t
- v = λ/T (they are equivalent to ‘d/t’ in the context of waves)
- v = λ/1 * 1/T
- λƒ
Name all the Wave Phenomena.
- Reflection
- Refraction
- Diffraction
- Interference
- Polarisation
Polarisation is exclusive to Transverse Waves.
How does the Ripple Tank demonstrate various wave effects?
- Since wavelength and frequency are inversely proportionate, they both depend on the frequency of the wooden plank oscillations.
- Wave speed depends on the depth of the medium the oscillations take place in (water).
- The wave speed is inversely proportionate to the depth of the medium.
