double split experiment - coherence and fringes Flashcards
what is coherence
two waves which have a constant phase difference
same wavelength
same frequency
same speed
what must waves have to have a constant phase
same frequency
same wavelength
how can we ensure coherence
use a colour filter - so the light has the same frequency
pass through a single slit - behaves like a single source of light
what type of source is a laser
single source
As the amplitude of a wave increases the intensity of the wave..
increases.
As the amplitude of a wave increases, intensity also increases. So constructive interference will result in…
waves with the maximum possible intensity
As the amplitude of a wave increases, intensity also increases. So destructive interference will result in…
waves with the minimum possible intensity
on the fringes where the intensity is at a maximum
in the center due to constructive interference
what is at the minima
minimum intensity due to destructive interference
how are maxima produced
two waves meet at a point where the path difference is a full multiple-wavelength and an even multiple of pi, which superposes and undergo constructive interference to produce amplitudes of maximum intensity
how is the fringes displayed on a graph
central maxima is the highest peak
then low fringes on either side
the maxima are lower then central maxima and gradually decrease
same width
why isnt intensity at the minima 0
as the distance travelled increase the amplitude also decreases meaning the intensity decreases
if 2 waves travel different distances the amplitudes will be different meaning the resulting amplitude will be the minimum intensity but not equal 0
If two waves start a journey with the same amplitude and both waves travel the same distance before they interfere, their relative amplitudes will…
be equal.
If two waves start a journey with the same amplitude and both waves travel different distances before they interfere, their relative amplitudes will…
not be equal.
