SHM explain
a = -ω^2 x
mention restorative force towards equlibrium
Give 3 examples of forms of interference
- If the resulting wave is larger than the component waves, the interference is “ Constructive”
- If the resulting wave is smaller than the component waves, the interference is “ destructive”
- If the wave has zero amplitude, the interference is “totally destructive”
Difference between diffraction grating and two slit interference and why?
- Peaks much brighter because: more sources
- Peaks all have equal intensity because: every peak is the middle of a set
- peaks are narrower because: destructive interference becomes more likely
What does the principle of superposition predict
It predicts the resultant wave of interference
What are rays and wavefronts
- A ray is a line showing the path/direction of a wave
- A wavefront is a line connecting all the points of the medium that are transmitting the same signal at the same time. They move forward through space
Explain Snells’s Law
When rays move between media, their speed changes. That causes the wave to “bend” –> REFRACTION. This can be put in an equation which is the Snells’ law. (n1/n2) = (sinθ2 / sinθ1) = (v2/v1)
What’s an index of refraction?
n= c/v
c = speed of light in vacuum
v = speed of light in the particular medium
What is Reflection
the change of direction of an incident ray when it meets a boundary. When the wave meets, it creates an angle of incidence to the normal, and when reflected, an angle of reflection appears. Note: The angle of incidence is equal to the angle of reflection
Longitudinal waves is when the direction of the oscillations is _______ to the direction the wave travels
parallel
How does a Standing wave happen
It happens when two waves with similar amplitude and frequency pass through each other in opposite directions. They involve a matter wave reflecting from a boundary and interfering with the incident waves as they pass through the medium.
Waves ____ pass through openings smaller than themselves (than the wavelength), and once a wave has been created, its frequency _____ change, it’s like the wave’s DNA.
cannot
refraction is…
when a light wave makes an angle of incidence with a boundary that is not perpendicular to it, and the direction of the wave changes as it enters this second medium.
