Between the two light waves from the two slits 1 φ 5

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between the two light waves from the two slits? 1. φ = 5 π, δ = 5 λ 2. φ = 5 π, δ = 5 λ 2 3. φ = π, δ = λ 2 4. φ = 2 π, δ = λ 5. φ = 4 π, δ = 4 λ 6. φ = 2 π, δ = 2 λ 7. φ = 4 π, δ = 2 λ 8. φ = π, δ = λ 9. φ = 3 π, δ = 3 λ 2 correct 10. φ = 3 π, δ = 3 λ Explanation:
Version 036 – Midterm 01 – yao – (56125) 5 For dark fringes, the phase angle difference φ is given by φ = π, 3 π, 5 π, ... For the 2 nd minimum, φ = 3 π and the corresponding path difference is δ = 3 π 2 π λ = 3 λ 2 . 011 10.0points A beam of light is diffracted by a single slit. The distance between the positions of zero intensity ( m = ± 1) is 3 . 87 mm. 1 . 935 mm 1 . 989 m 0 . 558 mm S 1 S 2 θ viewing screen Estimate the wavelength of the laser light. Use a small angle approximation sin θ = tan θ . 1. 619.505 2. 580.284 3. 588.259 4. 529.26 5. 567.76 6. 631.727 7. 542.851 8. 609.915 9. 597.343 10. 647.777 Correct answer: 542 . 851 nm. y L a S 1 S 2 θ viewing screen The distance y m from the m th minimum to the center of the first-order maximum can be calculated from the formulae sin θ m = a , tan θ m = y m L . In the small angle approximation, when θ is in radians sin θ = tan θ = θ = y m L = m λ a y m = m λ L a . The spacing between the minima m = 1 and m = 1 is equal to b = 2 y 1 = 2 λ L a λ = a b 2 L = 1 2 (0 . 000558 m) 0 . 00387 m 1 . 989 m × 10 9 nm m = 542 . 851 nm . 012 10.0points If the object distance for a converging thin lens is more than twice the focal length of the lens, the image is
Version 036 – Midterm 01 – yao – (56125) 6 4. located at a distance more than 2 f from the lens. 5. virtual and erect. Which of the glass lenses above, when placed in air, will cause rays of light (par- allel to the central axis) to diverge ?
014 10.0points
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