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1. A point source of wavelength 500nm is placed 5.0 m away from the zone platewhose central zone has the diameter 2.3 mm. Find the position of the primaryimage.

2. A zone plate is constructed in such a way that the radii of the circles which definethe zones are the same as the radii of Newtons dark rings formed between a plane

surface and surface having radius of curvature of 2.0 m. a) Find the primary focallength of the zone plate and b) secondary foci

3. Monochromatic light of wavelength 441 nm falls on a narrow slit on a screen 2.16maway, the distance between the second minimum and the central maximum is 1.62cm (a). calculate the angle of diffraction of the second minimum (b). find the widthof the slit

4. Light of wavelength 633 nm is incident on a narrow slit. The angle between the 1st

minimum on one side of the central maximum and the 1st minimum on the otherside is 1.97. Find the width of the slit.

5. A plane wave, with wavelength 593nm falls on a slit of width 420 m. A thinconverging lens having a focal length of 71.4 cm is placed behind the slit andfocuses the light on a screen. Find the distance on the screen from the center ofthe pattern to the second minimum

6. In a single slit diffraction pattern the distance between the 1st minimum on the rightand the 1st minimum on the left is 5.2 mm. The screen on which the pattern isdisplayed is 82.3 cm from the slit and the wavelength is 546 nm calculate the slitwidth.

7. Calculate approximately the relative intensities of the maxima in the single slitFraunhofer diffraction pattern.

8. In a double slit experiment, the distance D of the screen from the slits is 52cm, thewavelength is 480nm, the slit separation is 0.12mm and the slit width is 0.025mm(a) what is the spacing between adjacent fringes (b) what is the distance from thecentral maximum to the first minimum of the fringe envelope

9. The wall of a large room is covered with acoustic tile in which small holes are drilled5.2mm from the center to the center. How far can a person be from such a tile and

still distinguish individual holes assuming ideal conditions? Assume the diameter ofthe pupil of the observers eye to be 4.6mm and the wavelength to be 542nm .

10.The two head lights of an approaching automobile are 1.42 m apart. At what (a)angular separation and (b) maximum distance will the eye resolve them? Assume apupil diameter of 5 mm and a wavelength of 562 nm. Also assume that thediffraction effects alone limit the resolution.

11.A certain grating has 104 slits with a spacing d = 2100 nm. It is illuminated with alight of wavelength 589 nm. Find (a) The angular positions of all principal maximaobserved and (b) the angular width of the largest order maximum

12.A diffraction grating has 104 rulings uniformly spaced over 25 mm. It is illuminatednormally using a sodium lamp containing two wavelengths 589.0 and 589.59 nm.

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(a) At what angle will the first order maximum occur for the first of thesewavelengths?(b). what is the angular separation between the first order maxima for these lines.

13.A diffraction grating has 1.2 x 104 rulings uniformly spaced over a width w = 2.5 cmand is illuminated normally using sodium light containing two wavelengths 589 and

589.59nm. (a) at what angle does the first order maximum occur for the first ofthese wavelengths (b) what is the angular separation between these two lines inthe first order (c) how close in wavelength can two lines be in the first order andstill be resolved by this grating (d) how many rulings can a grating have and justresolve the sodium doublet lines.

14. A plane transmission diffraction grating has 200 rulings/mm and the principal

maximum is noted at 28. What are the possible wavelengths of the incident visiblelight?

15. A grating has 40,000 rulings spread over 76 mm. (a) What is its expected

dispersion D in /nm for sodium light ( = 589 nm) in the first three orders? (b) Whatis its resolving power in these orders?