Waves Flashcards
(63 cards)
Green, Red, Yellow, Blue, Orange, Indigo and Violet. Rank in terms of increasing wavelength.
Violet, indigo, blue, green, yellow, orange, red.
When ___ along a wave are undergoing the same ___ at the same ___ they are said to be in ___.
Points. Motion. Time. Phase.
Points exactly in phase will be ___ apart. Points exactly out of phase will be an ___ apart.
Full wavelengths. Odd number of half wavelengths.
One wavelength = ___ degrees.
A quarter wavelength = ___ degrees.
A half wavelength = ___ degrees.
360
90
180
Angle of incidence
Angle between incident ray and normal.
Angle of reflection
Angle between reflected ray and normal.
When a wave/pulse crosses a boundary into a different medium, the transmitted and reflected wave’s frequency remains ___, but both the ___ and ___ change.
Constant. Speed. Wavelength.
A wave/pulse moving from a heavier medium across a boundary into a lighter medium
The reflected wave/pulse is the ___ way up with ___ phase change and it ___ in the heavy medium so has the same speed and wavelength, but ___ amplitude in comparison to the ___ wave.
The transmitted wave is the ___ way up with ___ phase change, but passes into the ___ medium so has ___ speed and ___ wavelength as ___. Transmitted wave has ___ amplitude in comparison to the ___ wave.
For both transmitted and reflected waves, the ___ remains unchanged.
Same. No. Remains. Reduced. Incident.
Same. No. Lighter. Increased. Increased. v = fλ and f is constant. Reduced. Incident.
Frequency
A wave/pulse moving from a lighter medium across a
boundary into a heavier medium
The reflected wave is ___ with ___ phase change. It ___ in the light medium so has the ___ speed and wavelength, but reduced ___ in ___ to the incident wave
The transmitted wave is the ___ way up with ___ phase change, but passes into the heavier medium so has ___ speed and so ___ wavelength (as f = v/λ), and ___amplitude in comparison to the ___ wave.
For both transmitted and reflected waves, the frequency remains ___.
Inverted. 180 degree. Same. Amplitude. Comparison.
Same. No. Lower. Lower. Reduced. Incident.
Constant.
Waves travel ___ in shallower mediums.
Waves travel ___ in mediums with less tension.
Waves travel ___ in lighter mediums.
Faster
Slower
Faster
When a wave crosses a ___ into a different ___, its ___ and ___ changes. ___ remains constant.
Boundary. Medium. Speed. Wavelength. Frequency.
If a wave slows down when crossing a boundary, then its direction will bend ___ the normal.
If a wave speeds up when crossing a boundary, then its direction will bend ___ from the normal.
Towards
Away
Higher refractive index means waves move ___.
Lower refractive index means waves move ___.
Slower
Faster
Longer wavelengths will ___ ___ than shorter wavelengths
Diffract more
Longer wavelengths means ___ frequency
Lower
A gap much larger than the wavelength causes ___ diffraction.
A gap ___ to the wavelength causes a lot of diffraction.
More
Similar
Young’s double slit experiment provided evidence that light has ___ properties because a single monochromatic light source shone through two slits produced an ___ just like other waves.
Wave-like. Interference pattern.
Why do bright and dark bands form on the screen for an interference pattern?
Bright bands form on the screen where the light waves are in phase (whole number of wavelengths apart) and so interfere constructively. It is where an anti-nodal line intersects/meets the screen.
Dark bands form on the screen where the light waves are
exactly out of phase (odd number of half wavelengths apart) and so interfere destructively. It is where a
nodal line intersects/meets the screen.
What is required for interference patterns to form?
If two waves with the same frequency, wavelength, and
amplitude overlap.
dsinθ = nλ
Explain symbols.
d = distance between slits. θ = angle from central band to "n" band. n = order of bright band or loud noise. λ = wavelength.
How to find distance from central band to the “n” band?
Use trig
How to find maximum “n” band visible if you know the wavelength and distance between slits?
Assume theta is 90 degrees, that is the max angle from central band to “n” band to be visible on the screen.
sinθ = nλ/d. nλ/d can only be equal to sin90 (1) or lower, otherwise won’t be visible on screen. That’s why it is max value of n.
How to find minimum distance between slits if you know the “n” and wavelength. .
Assume theta is 90 degrees, that is that is the max angle from central band to “n” band to be visible on the screen.
sinθ = nλ/d. nλ/d can only be equal to sin90 (1) or lower, otherwise won’t be visible on screen. That’s why it is minimum value of distance between slits.
What is path difference?
The difference in the length of the path that two waves have to take to reach the same point.
