Procedure Part A 1)Place the light source on the 0.0 cm mark on the optical bench. 2)Place a lens holder at the 30.0 cm
Posted: Mon May 16, 2022 3:25 pm
Procedure Part A
1)Place the light source on the 0.0 cm mark on the optical
bench.
2)Place a lens holder at the 30.0 cm mark on the optical
bench.
3)Place the lens in the lens holder.
4)Place the screen on the optical bench and adjust its position
until a clear image forms on the screen.
5)Record the distance of the image from the lens.
6)Measure and record the height of the image on the screen.
7)Move the lens and holder to the 40.0 cm mark on the optical
bench. 8)Change the position of the screen until the image is again
clear on the screen.
1
9)Record the distance of the image from the lens.
10)Measure and record the height of the image on the screen.
11)Repeat steps 7 to 10 with the lens holder at the 50.0 cm
location on the optical bench.
12)Repeat steps 7 to 10 with the lens holder at the 60.0 cm
location on the optical bench.
13)Using the object and image distances, calculate the focal
length of the lens for each of the lens positions in Part A.
14)Using the height of the image and the height of the object,
calculate and record the magnifications for each of the lens
positions in Part A.
Data Tables for Part A
The focal length (based upon the manufacturer) is _____ 20.0 cm
______ Height of the object pattern on the light source is _____
3.4 cm ______
Object Distance
Image Distance
Image Height
Calculated Focal Length
Magnification
30.0 cm
61.6 cm
-7.0 cm
40.0 cm
40.7 cm
-3.5 cm
50.0 cm
33.7 cm
-2.3 cm
60.0 cm
30.5 cm
-1.7 cm
Note: a negative image height and/or a negative magnification
indicates that the image is inverted.
2
3
Procedure Part B
15)Fill in the table below with values you would get if you were
using a lens with a focal length of 10 cm.
Object Distance
Image Distance
Image Height
Magnification
30.0 cm
40.0 cm
50.0 cm
60.0 cm
16)Fill in the table below with values you would get if you were
using a lens with a focal length of 40 cm.
Object Distance
Image Distance
Image Height
Magnification
30.0 cm
40.0 cm
50.0 cm
60.0 cm
4
Procedure Part C
17)Place the screen in a holder at the 115.0 cm location on the
optical bench.
18)Place the laser pointer in a support clamp at the 0.0 cm
location on the optical bench.
19) Place the diffraction grating in a support clamp at the
105.0 cm location on the optical bench. (This gives a distance of
10.0 cm between the screen and the diffraction grating.)
20) Adjust the laser pointer in the support clamp so that it is
giving off light and that the light beam passes through the
diffraction grating.
21) At this time three red dots of laser light should show up
along a horizontal line on the screen. If they fall along a
vertical line, take the diffraction grating out of the support
clamp and rotate it 90 degrees and put it back into the support
clamp. If the three dots do not all fall on the screen adjust the
positions of the support clamps in the bases so that they do.
22) Using the meterstick, measure the distance between the
central dot and the two other dots. (If these distances are not the
same it means that the screen is not parallel to the diffraction
grating and parallel to the optical bench. If this happens, simply
adjust the support clamp holding the screen until the distances
from the central dot to the other two dots are the same.)
23) Record the distances from the central dot (zeroth-order
fringe) to the next set of dots (the first order fringe) in the
table provided.
24) Reset the support clamp for the diffraction grating so that
it is at the 100.0 cm location on the optical bench. (This gives a
distance of 15.0 cm between the screen and the diffraction
grating.)
25) Repeat the measurements described in steps 23 and 24.
26) Reset the support clamp for the diffraction grating so that
it is at the 95.0 cm location on the optical bench. (This gives a
distance of 20.0 cm between the screen and the diffraction
grating.)
5
27) Repeat the measurements described in steps 23 and 24.
28) Reset the support clamp for the diffraction grating so that
it is at the 85.0 cm location on the optical bench. (This gives a
distance of 30.0 cm between the screen and the diffraction
grating.)
29) Repeat the measurements described in steps 23 and 24.
L distance between diffraction grating and screen
s distance between central image and first bright dot
Θ
angle formed between central ray and first bright dot
D distance between lines etched into the diffraction grating
10.0 cm
5.9 cm
15.0 cm
8.9 cm
20.0 cm
11.8 cm
30.0 cm
17.7 cm
30) Calculate the separation angle and the distance between the
lines etched into the diffraction grating based upon each of the
four readings in the table above and enter these into the table
provided above. Please note: that the wavelength of light given off
by the laser pointers is listed on the laser pointers themselves.
Since it is given as a range of possible frequencies, simply use
the center frequency of the range listed.
(Note: the range listed on the laser pointer was 650 nm to 680
nm, so use a wavelength of 665 nm in your calculations.)
1)Place the light source on the 0.0 cm mark on the optical
bench.
2)Place a lens holder at the 30.0 cm mark on the optical
bench.
3)Place the lens in the lens holder.
4)Place the screen on the optical bench and adjust its position
until a clear image forms on the screen.
5)Record the distance of the image from the lens.
6)Measure and record the height of the image on the screen.
7)Move the lens and holder to the 40.0 cm mark on the optical
bench. 8)Change the position of the screen until the image is again
clear on the screen.
1
9)Record the distance of the image from the lens.
10)Measure and record the height of the image on the screen.
11)Repeat steps 7 to 10 with the lens holder at the 50.0 cm
location on the optical bench.
12)Repeat steps 7 to 10 with the lens holder at the 60.0 cm
location on the optical bench.
13)Using the object and image distances, calculate the focal
length of the lens for each of the lens positions in Part A.
14)Using the height of the image and the height of the object,
calculate and record the magnifications for each of the lens
positions in Part A.
Data Tables for Part A
The focal length (based upon the manufacturer) is _____ 20.0 cm
______ Height of the object pattern on the light source is _____
3.4 cm ______
Object Distance
Image Distance
Image Height
Calculated Focal Length
Magnification
30.0 cm
61.6 cm
-7.0 cm
40.0 cm
40.7 cm
-3.5 cm
50.0 cm
33.7 cm
-2.3 cm
60.0 cm
30.5 cm
-1.7 cm
Note: a negative image height and/or a negative magnification
indicates that the image is inverted.
2
3
Procedure Part B
15)Fill in the table below with values you would get if you were
using a lens with a focal length of 10 cm.
Object Distance
Image Distance
Image Height
Magnification
30.0 cm
40.0 cm
50.0 cm
60.0 cm
16)Fill in the table below with values you would get if you were
using a lens with a focal length of 40 cm.
Object Distance
Image Distance
Image Height
Magnification
30.0 cm
40.0 cm
50.0 cm
60.0 cm
4
Procedure Part C
17)Place the screen in a holder at the 115.0 cm location on the
optical bench.
18)Place the laser pointer in a support clamp at the 0.0 cm
location on the optical bench.
19) Place the diffraction grating in a support clamp at the
105.0 cm location on the optical bench. (This gives a distance of
10.0 cm between the screen and the diffraction grating.)
20) Adjust the laser pointer in the support clamp so that it is
giving off light and that the light beam passes through the
diffraction grating.
21) At this time three red dots of laser light should show up
along a horizontal line on the screen. If they fall along a
vertical line, take the diffraction grating out of the support
clamp and rotate it 90 degrees and put it back into the support
clamp. If the three dots do not all fall on the screen adjust the
positions of the support clamps in the bases so that they do.
22) Using the meterstick, measure the distance between the
central dot and the two other dots. (If these distances are not the
same it means that the screen is not parallel to the diffraction
grating and parallel to the optical bench. If this happens, simply
adjust the support clamp holding the screen until the distances
from the central dot to the other two dots are the same.)
23) Record the distances from the central dot (zeroth-order
fringe) to the next set of dots (the first order fringe) in the
table provided.
24) Reset the support clamp for the diffraction grating so that
it is at the 100.0 cm location on the optical bench. (This gives a
distance of 15.0 cm between the screen and the diffraction
grating.)
25) Repeat the measurements described in steps 23 and 24.
26) Reset the support clamp for the diffraction grating so that
it is at the 95.0 cm location on the optical bench. (This gives a
distance of 20.0 cm between the screen and the diffraction
grating.)
5
27) Repeat the measurements described in steps 23 and 24.
28) Reset the support clamp for the diffraction grating so that
it is at the 85.0 cm location on the optical bench. (This gives a
distance of 30.0 cm between the screen and the diffraction
grating.)
29) Repeat the measurements described in steps 23 and 24.
L distance between diffraction grating and screen
s distance between central image and first bright dot
Θ
angle formed between central ray and first bright dot
D distance between lines etched into the diffraction grating
10.0 cm
5.9 cm
15.0 cm
8.9 cm
20.0 cm
11.8 cm
30.0 cm
17.7 cm
30) Calculate the separation angle and the distance between the
lines etched into the diffraction grating based upon each of the
four readings in the table above and enter these into the table
provided above. Please note: that the wavelength of light given off
by the laser pointers is listed on the laser pointers themselves.
Since it is given as a range of possible frequencies, simply use
the center frequency of the range listed.
(Note: the range listed on the laser pointer was 650 nm to 680
nm, so use a wavelength of 665 nm in your calculations.)