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V0.61
LAB EXERCISE COTR - L1
DIFFRACTION AND INTERFERENCE OF LIGHT
Lab format: This lab exercise is performed with the lab kit.
Relationship to theory: This lab exercise explores the diffraction and Interference of light using a laser
and various slit configurations including a diffraction grating.
OBJECTIVES

The student will investigate the wave properties of light using a solid state laser, various slit
combinations, and a diffraction grating.
EQUIPMENT LIST
Lab Kit
 Solid State Laser
 2 Single edge razor blades
 Cornell Slit-film
 500 or 600 lines/mm diffraction-grating
 4 Bulldog Paper Clips
 Callipers
 Flat Mirror (front silvered would be best)
Student Supplied
 Solid Table that won’t wiggle
 White metric graph paper (5 to 10 sheets)
 Masking tape
 Measuring Tape, ruler,
and/or metre stick
 Level (if not part of the laser)
 Shims (slips of paper and/or
cardboard)
 Sharp pencil or mechanical
pencil for sketching
Figure 01: Lab Equipment
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INTRODUCTION
In this experiment, we will investigate the wave nature of light by stuΔing two effects -- diffraction and
interference. We will use these two effects to predict patterns given by single and multiple slits, and
calculate the slit spacing of a diffraction grating. Since we know the wavelength of the laser's red light
very precisely, we will use this to verify our calculations.
WARNINGS

Caution: Don't shine the intense laser light in anyone's eyes! Continuous exposure could cause
irreversible eye damage.

Don't get fingerprints on the Cornell Slit-film, or the Diffraction grating or their function could
be compromised. Handle them only by their edges. DO NOT clean them with Windex or a
similar product because the ammonia dissolves the film gelatine! If you must clean them use a
dry soft cotton cloth and don’t rub too hard.
The Cornell Slit-Film is glass and will break if dropped. Handle it carefully!

THEORY
A. INTERFERENCE
Electromagnetic waves act as a series of plane waves of the form:
E  t , x   E0 sin  2 ft  kx  ;
EQ L1.01
Where E is the amplitude of the electric field in volts/m at time t at some distance x, Eo is the peak
amplitude, f is the frequency of the wave in hertz (f = 1/T), k is the wave number (k= 2π/λ) which is the
phase angle in radians per metre and λ is the wavelength in metres (where λ= c/f = cT) and c is celerity,
the speed of light.
Like other electric and magnetic fields, light waves combine according to the principle of linear
superposition. If two light waves meet at some point at the same time then the electric field at that
point will be the vector sum of the individual fields. Their amplitudes add algebraically and the waves
may interfere:
1) Destructive Interference:
If two equal amplitude (sine) waves meet exactly out of phase by an optical path difference of ½λ
then they cancel and the net electric field there is zero.
2) Constructive Interference:
If two equal amplitude waves meet exactly in phase, then they combine and give a wave of double
amplitude.
B. DIFFRACTION
When parallel light waves pass a barrier, some light seems to flow into the geometric shadow. This
behaviour is called diffraction. It means that light can bend around corners and spread-out when
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passing through small openings. But the wavelength of light is very short, so diffraction is noticeable
only when light passes through extremely narrow slits, or sharply defined obstacles.
A laser is used so that these faint interference and diffraction effects become visible. It provides a very
bright plane wave-train that appears to come from infinity, having one pure colour of constant phase
(coherence) which keeps the pattern fixed in space.
The laser in the lab kit will be a solid state laser that emits light with a wavelength between about 630
nm to 650 nm. The one used during the writing of this lab exercise was a Jobmate Laser Level (model
57-5302-8) purchased from Canadian Tire. The one in your lab kit will be similar, but most likely will not
be identical. The lens that creates the line for the laser level has been removed so that this laser emits a
beam instead of a line. The one in your lab kit should not require this modification or will allow you to
set it to a beam.
Huygen's Construction Principle:
This model is used to show the wave nature of
diffraction. If we place a row of point sources along
a wavefront, then each point gives rise to a circular
wavelet that adds to the other wavelets to produce
the familiar parallel wavefront. See Figure 02. We
only use the forward facing halves of the circular
wavelets: the back halves are ignored since they are
going in the opposite direction (and would imply the
wavefront was travelling the other way).
Figure 02: A Plane Wave as a Row of Expanding Circles
Figure 03: Half Barrier Diffraction comparing Huygens Construction to a Ripple Tank Photo
In Figure 03 where the light-wave meets a sharp half barrier, the edge of the wavefront passing the
barrier acts as a point source sending circular patterns into the shadow behind the barrier.
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The light is bright in the central region. But on closer inspection a variation in brightness can be
observed where the parallel waves interfere with the circular waves and give a pattern of fine lines. This
effect can be seen by shining a laser beam on the edge of a razor blade.
C. Single-Slit Diffraction
Figure 04: Single Slit Diffraction Pattern
A pattern appears when we send a plane wave through a small slit of width w, which we call a
diffraction pattern. Let’s find the distance y from the centre of the slit to the first minimum in the
pattern. To do this, light from the centre must destructively interfere with light from the edge of the
slit. The distance travelled by these two waves must differ by exactly half a wavelength (λ/2). Referring
to Figure 04, since the slit width w is very small, and the distance r from slit to screen is very large in
comparison, then we can assume the ray paths AQ, CQ and DQ are parallel. Thus we can draw a line AB
perpendicular to the ray paths to create a similar triangle ABC to triangle CPQ, in which the angle  is
the same. Then, to relate  and λ at the first minima, from the small triangle we get:
sin  
/2


;
w/2 w
and thus   wsin  ;
EQ L1.02
EQ L1.03
If we increase path difference CB by nλ/2, the general form is:
n  wsin  ; {where n is an integer}
EQ L1.04
Here, a minima occurs where n is odd, a maxima where n is even.
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2n
 ;(n  1, 2,3,...) for minima
2
 2n  1 ;(n  1, 2,3,...) for maxima
w sin  
2
w sin  
EQ L1.05
EQ L1.06
Continuing to find the distance y along the screen to the first minima when r  y , then tan   sin  .
Using the big triangle CPQ:
tan  
y
r
; so for sufficiently small  y  r tan   r sin  
r
w
EQ L1.07
thus for the first minima:
y
r
;
w
EQ L1.08a
For the second minima:
y
2r
;
w
EQ L1.08b
And for the nth minima:
y
nr
; n  1, 2,3,... ;
w
EQ L1.08c
Notice that the differences between adjacent minima (and indeed the maxima) are all
r
so if we
w
measure the difference between one minima (or maxima) and the next we will have:
y  yn  yn 1  n
r
r
r r
  n  1
  n   n  1 

;
w
w
w
w
EQ L1.09
This will allow us an easier way to make accurate measurements of the patterns produced.
The intensity, I, (advanced: see textbook) can be given by:
I  I0
where

sin 2  / 2 
 / 2 
2 w sin 

2
;
.
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EQ L1.10
EQ L1.11
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D. Double-Slit Interference and Diffraction Pattern
Figure 05: Double Slit Diffraction Pattern
For the double-slit, like the single-slit we get minima and maxima when the path difference is nλ:
n  d sin  ;
EQ L1.12
where d is the centre to centre slit separation and tan  
y
 y
   tan 1   ;
r
r
Using the same approximation for small  as above, we can show that:
y
nr
;
d
EQ L1.13a
r
;
d
EQ L1.13b
and that
y 
Using wave superposition, the relative intensity I of the pattern compared to the central
maximum intensity ( I 0 ) is:
I  4I0
sin 2  / 2 
 / 2 
2
1 
cos 2    ;
2 
EQ L1.14
where α is the phase difference of the slit width:  
and δ is the phase difference between slits:
2 w sin 

2 d sin 


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EQ L1.15
EQ L1.16
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Figure 06: Combined Single Slit and Double Slit Wave Pattern Shown at Top, Separate Components Below.
This means that there are really two underlying wave patterns competing; the single-slit pattern (see
Figure 04) and a double-slit pattern that is modulated by the single-slit pattern.
Shown in Figure 06 is a graph (done with Richard Hewko's PLOT2D program) which plots the intensity
equations for a double-slit pattern with width w = 8λ and separation d = 26λ. Io was assigned a value of
1 to give relative intensity along the y-axis.
The combined wave pattern is shown at the top then the two underlying wave patterns are separated
out and shown below.
E. Multiple-Slit Diffraction Patterns
Figure 07: Interference Pattern of Equally Spaced Sources
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For three slits, there is a small secondary maxima between each pair of principal maxima, and the
principal maxima are sharper and more intense than those produced by just two slits.
For four slits, there are two small secondary maxima between each pair of principal maxima, and their
principal maxima are even more narrow and intense. In general, as the number of slits (N) increase, the
principal maxima become sharper, with their intensity proportional to N² relative to a single-slit.
Secondary maxima become fainter.
Diffraction Gratings:
When we have hundreds of slits then we have a diffraction grating which gives sharp and precise
principal maxima without distracting secondary maxima: these are used in optical instruments like
spectrometers. For a diffraction grating, the formula is similar to the double-slit, but with just the
distance d between slits required.
n  d sin  ;
EQ L1.17
Where d is distance between slits,  is the angle of diffraction, and n identifies one of the principal
maxima (0,1,2,3...). Here n = 0 identifies the 0th order maxima (which goes straight through), 1 the firstorder principal maxima, 2 the fainter second-order, up to about the third or fourth-order. Usually only 2
or 3 maxima exist.
Again, we can show that for sufficiently small  :
y
nr
;
d
EQ L1.18a
r
d
EQ L1.18b
and that
y 
The previous equations all assume the incident beam is perpendicular to the grating: but if it is not, then
an error correction is applied:
n  d  sin   sin   ;
EQ L1.19
where  is the incident angle.
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SUMMARY
For all the above cases the maxima are determined by the formula:
n  d sin  ;
EQ L1.20
Where n represents the order of the bright fringe (0,1,2,3...), and d is the aperture distance (the distance
between slits for double-slits & diffraction gratings, and the slit width for a single-slit).
For sufficiently small  :
y 
r
;
d
EQ L1.21
PROCEDURE
1) Place the table close to or against the wall you intend to use. Use the carpenter’s level (or, if
you are using a laser level, use the levels built into the laser level) and the shims to make sure
the table is as level as possible. Also use the shims to make sure the table does not ‘wobble’
when you lean on it.
Figure 08: Levels
2) Turn on the laser. Caution: don't shine the intense laser light in anyone's eyes! Place the laser
at the end of the table farthest from the wall and make sure it is close to level (if the table top is
level then this should not be difficult). Aim it at the wall making sure the laser beam is
approximately perpendicular to the wall.
3) Tape the flat mirror to the wall where the laser beam will strike its approximate centre. (Be sure
to use masking tape so that you don’t accidentally remove the paint when you remove the
mirror. Painter’s masking tape would be best.)
4) You want to adjust the aiming of the laser so that the beam reflects off the mirror and back into
the laser. Use the white card to determine where the beam is reflecting. If it is reflecting to the
left or right of the laser move it so that the beam is reflecting back in the same vertical plane as
the laser is shining in. This is very important for this lab exercise to work properly. Now adjust
the laser’s level so the reflected beam shines back into the laser’s aperture. The vertical
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alignment isn’t as critical as the horizontal alignment, but be as accurate as you can anyway.
From now on be careful not to disturb the alignment of the laser. If you accidentally bump it,
then repeat steps 3 and 4 to make sure the laser beam is perpendicular to the wall before
proceeding.
Figure 09: Mirror taped to wall and laser beam re-entering the laser aperture
5) Remove the mirror from the wall and tape a white piece of metric graph paper to the wall in its
place so that the laser beam is shining at the approximate middle of the paper near the top.
Figure 10: Laser aimed at
Graph Paper on the wall
Part 1: Half Barrier and Single Slits
Note - The images below are provided only to give you an example of what you should see. They should
not be used as your data.
6) Place a razor blade into a clip as shown in Figure 11 to create a half barrier and position it in the
laser beam so that the razor blade edge blocks about half of the laser beam. Make sure the
plane of the razor blade is as close to perpendicular to the laser beam as possible. Notice how a
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sharp edge will bend light around corners (see Figure 03). Use your pencil to trace the pattern
you see on the graph paper noting which side of your sketch is the same as the side the razor
blade is on. Why are there dark vertical lines on just one side? Label this tracing “Half Barrier
Pattern”
Figure 11: Razor blade splitting laser beam
Figure 12: Half Barrier Pattern
7) Move the graph paper up a couple of cm and re-tape it to the wall. Mount the second razor
blade as before and position the 2 razor blades such that they create a slit. See figure 13. Vary
the distance between the 2 razor blades and watch what happens to the pattern. Is this what
you expected? When you get a pattern that looks something like figure 14, sketch it.
Figure 13: Razor blades forming a single slit
Figure 14: Razor Blade Single Slit Pattern
8) Move the graph paper up a few cm and re-tape it to the wall.
a. Now position the 0.75 mm single slit on the Cornell Slit-film in the path of the laser
beam so that the beam passes through that slit. (See Appendix 1: The Cornell Slit-film to
determine which slit pattern you should be using.) You may need to use various
thickness books to get correct slit into the path of the laser beam. Now you have two
wave patterns, one from each side of the slit, interfering to give distinct red and dark
bands as shown in Figure 04. Trace the pattern you see on the graph paper with your
pencil and label it “0.75 mm Slit Pattern”.
b. What happens to the dark band spacing when you replace the 0.75 mm slit with the 1.5
mm slit? Move the paper up a couple of cm again, trace this pattern, and label it “1.5
mm Slit Pattern”.
c. What happens if you replace the 1.5 mm slit with the 0.5 mm slit? Again move the
graph paper up a couple cm, trace this pattern, and label it “0.5 mm Slit Pattern”.
d. Repeat this process for the 0.25 mm and 0.13 mm slits as well.
e. In each case is the central bright fringe twice the width of any other bright fringe in each
case? (Figures 15 to 24 give examples of what you should see. Your eye will pick out
more detail than these images reveal.)
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Figure 15: 0.75 mm Single Slit
Figure 16: 0.75 mm Single Slit Pattern
Figure 17: 1.5 mm Single Slit
Figure 18: 1.5 mm Single Slit Pattern
Figure 19: 0.5 mm Single Slit
Figure 20: 0.5 mm Single Slit Pattern
Figure 21: 0.25 mm Single Slit
Figure 22: 0.25 mm Single Slit Pattern
Figure 23: 0.13 mm Single Slit
Figure 24: 0.13 mm Single Slit Pattern
Part 2: Multiple Slits
Note - Make sure the laser beam is still perpendicular to the wall by repeating steps 3 and 4 if necessary.
9) Tape a new piece of graph paper to the wall so that the laser beam strikes it near the centre top.
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10) Place the 0.10 mm slit in the path of the laser beam making sure the slit-film is perpendicular to
the beam. You can check this by positioning the slit-film so that the reflected portion of the
beam reflects back into the laser aperture. Arrange the graph paper so that the pattern is
parallel to one of the horizontal grid lines. Measure the ‘radius’ from the slit-film to the paper.
This is ‘r’. Trace the pattern on the graph paper and use the Vernier callipers to measure the
distance (Δy) between adjacent dark fringes near the centre of the pattern and record this on
the graph paper for later. Label this trace “0.10 mm Slit Pattern”. Compare this pattern to the
patterns obtained in Part 1.
Figure 25: Equipment
Figure 26: 0.10 mm Single Slit
Figure 27: 0.10 mm Single Slit Pattern
11) Move the graph paper up a couple of cm, and place the double slit (w = 0.10 mm and d = 0.20
mm) in the path of the laser beam making sure the slide is perpendicular to the beam, and the
slits are vertical. Measure the radius from the slit-film to the graph paper. Trace this pattern on
the graph paper and measure the distance (Δy) between adjacent dark fringes near the centre of
the pattern with the callipers. Label this trace “Double Slit Pattern; w = 0.10 mm; d = 0.20 mm”.
Figure 28: Double Slit; w = 0.10 mm; d = 0.20 mm
Figure 29: Double Slit; w = 0.10 mm; d = 0.20 mm Pattern
12) Move the graph paper up a couple of cm, and place the double slit (w = 0.10 mm and d = 0.40
mm) in the path of the laser beam making sure the slide is perpendicular to the beam, and the
slits are vertical. Measure the radius (r) from the slide to the screen. Trace this pattern on the
graph paper and measure the distance (Δy) between adjacent dark fringes near the centre of the
pattern with the callipers. Label this trace “Double Slit Pattern; w = 0.10 mm; d = 0.40 mm”.
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Figure 30: Double Slit; w = 0.10 mm; d = 0.40 mm
Figure 31: Double Slit; w = 0.10 mm; d = 0.40 mm Pattern
13) Move the graph paper up a couple cm, and place the double slit (w = 0.10 mm and d = 0.70 mm)
in the path of the laser beam making sure the slide is perpendicular to the beam, and the slits
are vertical. Measure the radius from the slit-film to the graph paper. Trace this pattern on the
graph paper and measure the distance (Δy) between adjacent dark fringes near the centre of the
pattern with the callipers. Label this trace “Double Slit Pattern; w = 0.10 mm d = 0.70 mm”.
Figure 32: Double Slit; w = 0.10 mm; d = 0.70 mm
Figure 33a: Double Slit; w = 0.10 mm; d = 0.70 mm Pattern
Figure 33b: Double Slit; w = 0.10 mm; d = 0.70 mm Pattern Detail
Note: Be careful to measure the close-spaced double-slit pattern separation, not the wider-spaced
single-slit brightness variation pattern: see Figures 05 and 06 and Figure 33b for a picture of the detail.
Beware; if you slightly move the laser beam to cover only half of the double-slit, you get just the singleslit pattern.
What happens to the pattern when the double-slits are wider apart? You should see a
combined single-slit/double-slit pattern as in Figure 06. Also note the detail in Figure 33b.
14) Tape a new piece of graph paper to the wall so that the unimpeded laser beam is centred near
the top. Place the 3-slit (w = 0.06 mm and d = 0.13 mm) in the path of the laser beam making
sure the slide is perpendicular to the beam, and the slits are vertical. Measure the radius from
the slide to the screen. Trace this pattern on the graph paper and measure the distance (Δy)
between adjacent dark fringes near the centre of the pattern with the callipers. Label this trace
“3-Slit Pattern; w = 0.06 mm d = 0.13 mm”.
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Figure 34: 3-Slit; w = 0.06 mm; d = 0.13 mm
Figure 35: 3-Slit; w = 0.06 mm; d = 0.13 mm Pattern
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15) Move the graph paper up a couple of cm, and place the 4-slit slide (w = 0.06 mm and d = 0.13
mm) in the path of the laser beam making sure the slide is perpendicular to the beam, and the
slits are vertical. Measure the radius from the slide to the screen. Trace this pattern on the
graph paper and measure the distance (Δy) between adjacent dark fringes near the centre of the
pattern with the callipers. Label this trace “4-Slit Pattern; w = 0.06 mm d = 0.13 mm”.
Figure 36: 4-Slit; w = 0.06 mm; d = 0.13 mm
Figure 37: 4-Slit; w = 0.06 mm; d = 0.13 mm Pattern
16) Move the graph paper up a couple of cm, and place the 40-slit diffraction grating (w = 0.06 mm
and d = 0.06 mm) in the path of the laser beam making sure the slide is perpendicular to the
beam, the beam passes through the centre of the grating, and the slits are vertical. Measure the
radius from the slide to the screen. Trace this pattern on the graph paper and measure the
distance (Δy) between adjacent dark fringes near the centre of the pattern with the callipers.
Label this trace “40-Slit Grating Pattern; w = 0.06 mm d = 0.06 mm”.
Figure 38: 40-Slit; w = 0.06 mm; d = 0.06 mm
Figure 39: 40-Slit; w = 0.06 mm; d = 0.06 mm Pattern
17) Move the graph paper up a couple of cm, and place the 80-slit diffraction grating (w = 0.02 mm
and d = 0.06 mm) in the path of the laser beam making sure the slide is perpendicular to the
beam, the beam passes through the centre of the grating, and the slits are vertical. Measure the
radius from the slide to the graph paper. Trace this pattern on the graph paper and measure
the distance (Δy) between adjacent dark fringes near the centre of the pattern with the
callipers. Label this trace “80-Slit Grating Pattern; w = 0.02 mm d = 0.06 mm”.
Figure 40: 80-Slit; w = 0.02 mm; d = 0.06 mm
Figure 41a: 80-Slit; w = 0.02 mm; d = 0.06 mm Pattern
Figure 41b: 80-Slit; w = 0.02 mm; d = 0.06 mm Pattern
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18) Examine the 40 & 80-slit patterns. How does maxima spacing and sharpness change as the
number of slits increase?
Part 3. The Diffraction Grating:
19) Make sure the laser is still perpendicular to the wall by holding the mirror flat against the wall
and make sure the reflected beam still reflects back into the laser aperture. If it does not then
repeat steps 3 and 4 now. Our diffraction equation assumes the laser beam is set normal to the
wall, so it is critical that the beam is perpendicular to the wall.
20) Tape a new piece of graph paper in ‘landscape’ orientation1 to the wall so that the laser beam
strikes it in the centre near the top. (1The long dimension of the graph paper is horizontal. )
21) Place the provided diffraction-grating (probably 500 lines/mm. but check it) in the path of the
laser beam making sure the grating is perpendicular to the beam, the slits are vertical, and the
laser beam passes through the approximate centre of the grating. (Be very careful not to get
fingerprints on the grating.) Move the diffraction grating closer to the wall being careful to keep
the beam passing through the approximate centre of the grating until you see 5 dots, one at
centre, the 1st order pair on either side, and the 2nd order pair further out. If you can see all 5
dots, but they are too close together you can move the diffraction grating back toward the laser
until the 5 dots have the maximum separation that you can use on your graph paper. Compare
this pattern to the patterns obtained in Parts 1 and 2.
22) Measure the radius (distance r) from the diffraction grating to the graph paper. Trace the
pattern on the graph paper and use the Vernier callipers or a ruler to measure the distance (Δy)
between the 0th order spot to the 1st order maxima spot and record this on the graph paper for
later. Measure the distance from the 0th order to the 2nd order as well and record this on the
graph paper. Label this trace “500 lines/mm diffraction-grating Pattern”.
Figure 42: 500 lines/mm Diffraction Grating
Figure 43: 500 lines/mm Diffraction Grating Pattern
23) Usually in this lab exercise you are given the exact wavelength of the laser light and asked to
calculate the actual number of lines/mm of the grating since this can vary due to temperature
variations and other environmental conditions. Since the laser each student may have will vary,
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we do not have this information for you. So, in this last step, assume the diffraction grating is
actually the stated value (probably 500 lines/mm) and calculate the wavelength of the light your
laser is emitting. Since the number of lines/mm can vary ±2% of the stated value, give an
uncertainty for your final answer based on this uncertainty and the uncertainty of your
measurements. Compare this to the wavelength of light your laser is rated at. (This should be
written on the laser somewhere. The one used to prepare this lab was rated at between 630
nm and 680 nm.)
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ANALYSIS AND/OR QUESTIONS
Experiment L1 Laboratory Results
Part 1: Half Barrier and Single Slits
Sketch and label the pattern you saw with the half barrier; then sketch the pattern for the 1.50, 0.75,
0.50, 0.25, and 0.13 mm single slits:
Pattern for
Pattern Sketches
Half Barrier
1-slit
w  1.50mm
1-slit
w  0.75mm
1-slit
w  0.50mm
1-slit
w  0.25mm
1-slit
w  0.13mm
Part 2: Multiple Slits
nominal distance
between slits
Pattern Sketch
Measured
Fringe
Separation
( y )
Radius
from Slit
to Screen
(r)
Calculated
Wavelength
( )
1-slit
w  0.10mm
2-slit
w  0.10mm d  0.20mm
2-slit
w  0.10mm d  0.40mm
2-slit
w  0.10mm d  0.70mm
3-slit
w  0.06mm d  0.13mm
4-slit
w  0.06mm d  0.13mm
40-slit
w  0.06mm d  0.06mm
80-slit
w  0.02mm d  0.06mm
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19
PHYSICS COURSE NAME
LAB x
Part 3: Diffraction Grating
# lines/mm = _______________________
Calculated from
lines/mm
Fringe Separation
(d)
(Δy)
Radius from the
Cornell Slit-film to
the Graph Paper
(r)
Calculated
Wavelength
(λ)
1st order right
1st order left
2nd order right
2nd order left
Best estimate for wavelength (λ):
_____
± ____
Creative Commons Attribution 3.0 Unported License
nm;
20
PHYSICS COURSE NAME
LAB x
REFERENCES
From Original Lab Exercise:
1. Tipler, Paul: Physics for Scientists & Engineers, 3rd Ed. Worth Publishers, 1991. ISBN 0-87901432-6. P951, 981, 1068, 1075.
2. Ohanian, Physics, p806, Chp 38 p861, Chp 39.4-5 p871, Chp 40.1
3. Mayfield Publishing Co., Directions for Using Cornell Slitfilm Demonstrator, 1987.
4. Pedrotti, Introduction to Optics 2nd Ed. Prentice-Hall 1993. ISBN 0-13-501545-6.
Original Lab Manual by Rick Nowel, E. Tech, COTR
Adapted for Remote Delivery by Ron Evans, MSc
Under the Remote Science Labs for Second Year Physics Project funded by BCcampus
2012 - 2013
Public domain images in Figures: 02, 03, 04, 05, 06, 07, and A1
were imported from the original lab manual that was produced by COTR.
All other images were produced by Ron Evans
and are covered by the CC license of this document.
Creative Commons Attribution 3.0 Unported License
21
PHYSICS COURSE NAME
LAB x
Appendix 1: The Cornell Slit-film
This is a map of the Cornell Slit-film. Use it to identify which slit pattern you are being asked to use.
Figure A1: This is a map of the Cornell Slit-Film that is included in your lab kit.
(Circled numbers indicate number of slits).
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22