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femaleinstemneedhelp
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- Homework Statement
- 1. Two coherent waves traveling along paths 2 µm apart collide at a point. Will the light with a wavelength of 400 nm at that point be amplified or diminished?
2. A diffraction grating is perpendicularly incident on light of 760 nm. A first-order diffraction maximum occurs at an angle of 10 degrees. How many strokes are there per millimetre of the diffraction grating?
- Relevant Equations
- d sin(θ) = mλ ; N = 1 / d
1 exercise: The light at that point will diminish.
Explanation:
Since the waves are coherent, their phase difference depends on the difference in distance travelled.
A path difference of 2 µm is equal to 5 wavelengths (λ = 400 nm).
When the phase difference of the waves is 5λ, they are in opposite phase and are attenuated when added together.
2 exercise:
We use the diffraction grating equation:
d sin(θ) = mλ
d is the width of the grid stroke
θ is the angle of the diffraction maximum
m is the order number of the diffraction maximum (in the first order m = 1)
λ is the wavelength of light
d = λ / (m sin(θ)) = 760 nm / (1 * sin(10°)) = 4374 nm
N = 1 / d = 1 / (4374 nm * 10^(-9) m/nm) = 1200 mm^(-1)
Answer: 1200 strokes?
I need help with figuring out if this is the correct way to solve these problems and if my answers are correct. I would be grateful for any type of assistance.
Explanation:
Since the waves are coherent, their phase difference depends on the difference in distance travelled.
A path difference of 2 µm is equal to 5 wavelengths (λ = 400 nm).
When the phase difference of the waves is 5λ, they are in opposite phase and are attenuated when added together.
2 exercise:
We use the diffraction grating equation:
d sin(θ) = mλ
d is the width of the grid stroke
θ is the angle of the diffraction maximum
m is the order number of the diffraction maximum (in the first order m = 1)
λ is the wavelength of light
d = λ / (m sin(θ)) = 760 nm / (1 * sin(10°)) = 4374 nm
N = 1 / d = 1 / (4374 nm * 10^(-9) m/nm) = 1200 mm^(-1)
Answer: 1200 strokes?
I need help with figuring out if this is the correct way to solve these problems and if my answers are correct. I would be grateful for any type of assistance.
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