Single Slit Diffraction

Question 1

Change in direction of propagation of light NOT due to reflection of refraction

Answer 1

Diffraction

Question 2

The deviation from rectilinear propagation that occurs when light advances beyond an obstruction

Answer 2

Phenomenon of diffraction

Question 3

Can we use snellls law to predict diffraction

Answer 3

No

Question 4

Diffraction at the edge of an aperture does what to images

Answer 4

Blurs images of objects

Question 5

What proved light is a wave?

Answer 5

Diffraction

Question 6

What is Huygens principle

Answer 6

All points on a wavefront can be considered as point sources for the production of spherical secondary wavelets, and at any later time the new wavefront position in the envelope (or surface of tangency) to these secondary wavefronts

Question 7

What is fresenels expansion on Huygens principle

Answer 7

For light in the same bundle (waves from the same point source) the secondary wavelets undergo mutual interference. Interfere constructively and destructively

Question 8

What is the ripple effect in the diffraction pattern due to?

Answer 8

The constructive and destructive interference of the secondary wavelets

Question 9

When a single slit is vertical, the waves are diffracted _______

Answer 9

Horizontally

Question 10

When a single slit is horizontal, the waves are diffracted ______

Answer 10

Vertically

Question 11

When a vertical slit is placed against a horizontal slit of the same width, the combo forms ________

Answer 11

A square aperture

Question 12

When a circular aperture is illuminated by a monochromatic plane wave, the waves are diffracted_________

Answer 12

Equally in all directions

Question 13

Wavelength of spruce equal to or larger than width of the slit (lambda > a), forms _________

Answer 13

Diffraction pattern

Question 14

For diffraction to occur, what is the relationship of d and a?

Answer 14

D should be larger than a

Question 15

Path difference in single slit diffraction

Answer 15

asin(theta)=m(lambda)

Question 16

What are the two types of diffraction?

Answer 16

• fresnel (near field) diffraction

- Fraunhofer (far-field) diffraction

Question 17

Fresnel (near field) diffraction

Answer 17

The source of light and the screen are at finite distance from the diffraction aperture

Can be converging or diverging, but not collimated

Question 18

Fraunhofer (far field) diffraction

Answer 18

The source of light and the screen are at an infinite distance from the diffraction aperture

Can be collimated

Question 19

Which type of diffraction is easy to observe and calculate the intensity distribution

Answer 19

Fraunhofer (far field) diffraction

Question 20

Bright in the center of a shadow, ex. Floaters in the eye

Answer 20

Poisson spot

Question 21

Near field diffraction

Answer 21

Fresnel diffraction

Question 22

Far field diffraction

Answer 22

Fraunhofer diffraction

Question 23

Finite distance from slit to screen

Answer 23

Fresnel diffraction

Question 24

Infinite distance from slit to screen

Answer 24

Fraunhofer diffraction

Question 25

Converging or diverging wave

Answer 25

Fresnel difffraction

Question 26

Plane waves

Answer 26

Fraunhofer diffraction

Question 27

Difficult to observe and calculate

Answer 27

Fresnel diffraction

Question 28

Easy to observe and calculate

Answer 28

Fraunhofer diffraction

Question 29

Diffraction patterns vary with distance (slit to screen)

Answer 29

Fresnel diffraction

Question 30

Insensitive to distance changes (maintains same angular relationship)

Answer 30

Fraunhofer diffraction

Question 31

Which type of diffraction yields a poisson spot?

Answer 31

Fresnel diffraction

Question 32

Combined effect of 2 slits and single slit interference

Answer 32

With 2 slits, not only will you see diffraction patterns due to individual single slits, but also interference patterns due to the waves coming from different slits

Question 33

The diffraction pattern acts as ________–, that _____________

Answer 33

• Envelope

- that controls the intensity of the regularly spaced interference maxima