1. Multiple-Choice Questions
Animals
Vision and
Diffraction
Multiple-Choice Questions
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2. Question 1 As two points on a piece of paper are moved
Vision and
Diffraction
Question 1
As two points on a piece of paper are moved
towards you how does the angle the points
make with respect to your eye change?
a) No change
Smaller
c) Larger
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3. Question 1 Solution As two points on a piece of paper are moved
Vision and
Diffraction
Question 1 Solution
As two points on a piece of paper are moved
towards you how does the angle the points
make with respect to your eye change?
a) No change
Smaller
c) Larger
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4. Question 2 How does the width (W) of the central maximum
Vision and
Diffraction
Question 2
How does the width (W) of the central maximum
formed from diffraction through a circular
aperture (pupil) change with aperture size (D)
for a fixed distance away from the aperture?
a) W increases as D increases
b) W decreases as D increases
c) W does not depend on D
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5. Question 2 Solution a) W increases as D increases
Vision and
Diffraction
Question 2 Solution
How does the width (W) of the central maximum
formed from diffraction through a circular
aperture (pupil) change with aperture size (D)
for a fixed distance away from the aperture?
Point source D θ1
a) W increases as D increases
b) W decreases as D increases
c) W does not depend on D
θ1=1.22 λ/D
As D increases θ1 decreases
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6. Question 3 Would you be able to resolve two points on a
Vision and
Diffraction
Question 3
Would you be able to resolve two points on a
piece of paper from further away with a
smaller or larger pupil?
a) Smaller
b) Larger
c) Pupil size doesn’t matter
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7. Question 3 Solution b) Larger θ1=1.22λ/D
Vision and
Diffraction
Would you be able to resolve two points
on a piece of paper from further away with
a smaller or larger pupil?
b) Larger
θ > θ1
θ = θ1
θ1=1.22λ/D
As diameter D of pupil
increases, min angle
of resolution θ1 decreases.
The points can be
further away and still resolvable
compared to a smaller pupil size. θ θ
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8. Question 4 What wavelength of light would you be able to
Vision and
Diffraction
Question 4
What wavelength of light would you be able to
resolve at the furthest distance based on
diffraction?
a) Red (λ = 650 nm)
b) Green ( λ = 550 nm)
c) Blue (λ = 450 nm)
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9. Question 4 Solution What wavelength of light would you be able to
Vision and
Diffraction
Question 4 Solution
What wavelength of light would you be able to
resolve at the furthest distance based on
diffraction?
a) Red (λ = 650 nm)
b) Green ( λ = 550 nm)
c) Blue (λ = 450 nm)
The min angle of resolution is θ1=1.22λ/D. As λ decreases θ1 decreases.
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10. Question 5 If the distance from your pupil to the back of
Vision and
Diffraction
Question 5
If the distance from your pupil to the back of
your eye increased would that change the
minimum angle of resolution?
a) Yes, it would decrease
b) Yes, it would increase
c) No, it would not change
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11. Question 5 Solution If the distance from your pupil to the back of
Vision and
Diffraction
Question 5 Solution
If the distance from your pupil to the back of
your eye increased would that change the
minimum angle of resolution?
θ1 constant,
width w
changes
a) Yes, it would decrease
b) Yes, it would increase
c) No, it would not change
The min angle of resolution is θ1=1.22λ/D which does not depend on the distance from the pupil to the back of the eye.
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