waves test study Flashcards
what does a progressive wave do
A progressive wave carries energy from one place to another
how many types of progressive waves are there
There are two types of progressive waves
longitudinal and transverse
Longitudinal waves have vibrations parallel to the direction in which the wave travels, whereas transverse waves have vibrations at right angles to the direction in which the wave travels
what is displacement
Displacement is the distance of a point on the wave from its undisturbed position or equilibrium position
what is amplitude
Amplitude is maximum displacement of a wave
what is wavelength
Wavelength is the distance between two adjacent points on a wave oscillating in step with each other.
what is period
Period is time taken for one complete oscillation of a point in a wave
what is frequency
Frequency is the number of oscillations per unit time of a point in a wave
what is phase difference
Phase difference is the fraction of a cycle between oscillating particles, expressed either in degrees or in radians
what phase difference do two points on a wave separated by a distance of one wavelength have
They have a phase difference of 0 or 360 degrees
what does the frequency f of a wave relate do
The frequency f of a wave is related to its period T by the equation
f = 1/T
What can the frequency of a sound wave be measured by
the frequency of a sound wave can be measured using a cathode ray oscilloscope (CRO).
The speed of all waves is given by what equation
wave speed = frequency x wavelength
v = fλ
what is the intensity of a wave
The intensity of a wave is defined as the wave power transmitted per unit area at right angles to the wave velocity
intensity = power/area
Intensity units
intensity has units of Wm-²
What is the Doppler effect
the Doppler effect is the change in an observed wave frequency when a source moves with speed Vs
What is what is the intensity of a wave directly proportional to
it is directly proportional to the square of the amplitude
What speed do all electromagnetic waves travel at
all electromagnetic waves travel at the same speed of 3.0 x 10^8 m s ^-1
In a vacuum, but they have different wavelengths and frequencies
electromagnetic waves are transverse waves
The regions of the electromagnetic spectrum in order of increasing wavelength are:
y-rays X-rays ultraviolet visible infrared microwaves Radio waves
How many places does a plane polarised wave have oscillations in
a plane polarised wave has oscillations in just one plane
What type of waves can be play polarised
only transverse waves can be plane polarised
Equation for Malus’s law
I = Io cos^2 0
Where I is the intensity of the transmitted light through the polarising filter, lo is the incident intensity of light and 0 is the angle between the transmission axis of the filter and the plane of polarisation of the incident light
