This exam consists of 28 questions; true-false questions are worth 2
points each, three-choice multiple choice questions are worth 3 points
each, five-choice multiple choice questions are worth 6 points each.
The maximum possible score is 107. When the exam was given, the mean
was 83.8; the median was 86. Click here to see the
formula sheet that came with the exam.
(c) Both concave and convex could produce this image.
What is the wavelength l of the incident
(a) l = 591 nm
(b) l = 654 nm
(c) l = 712 nm
(d) l = 759 nm
(e) l = 808 nm
An object is placed between the center of curvature, C, and the focal
point, F, of a concave mirror. Use ray-tracing techniques to locate the
The image will be found closest to:
(a) less than 1 cm
(b) also equal to 1 cm
(c) greater than 1 cm
An object is placed in front of a convex mirror as shown. (Warning:
incorrect answers can be obtained from the numbers in the problem.)
Where will the image be located with respect to the mirror?
(a) di = -24 cm
(b) di = +24 cm
(c) di = +120 cm
(a) M = -2.0
(b) M = -0.4
(c) M = +0.4
(d) M = +1.0
(e) M = +2.0
Which ray in the ray diagram above is not correct?
(a) to the left of the left focal point
(b) between the left focal point and the lens
(c) between the right focal point and the lens
(d) at the right focal point
(e) to the right of the right focal point
A converging lens and a diverging lens are placed as shown in the
figure above, 12 cm apart. The converging lens is located at the
origin. An object is located at –50 cm.
Where along the principle axis is the location of the image formed
by only the first lens?
(a) -38.2 cm
(b) –12.5 cm
(c) +33.3 cm
(a) -33.3 cm
(b) -17.0 cm
(c) -6.8 cm
(d) +5.6 cm
(e) +29.7 cm
(a) n1 < n2 < n3
(b) n1 < n3 < n2
(c) n2 < n3 < n1
In the figure to the right, a light beam starts from the lower left
corner, in air, enters a box with a transparent material inside,
strikes a mirror and reflects, then exits the box back into the air
along the direction shown.
If the index of refraction of the material in the box is increased
from nstuff = 1.4 to nstuff = 1.6, the distance L
(c) remain the same.
(a) L = 6.39 cm
(b) L = 7.14 cm
(c) L = 8.05 cm
(d) L = 8.88 cm
(e) L = 9.32 cm
A man requires bifocals to correct both his near and far vision
problems. Consider the bifocals to be a pair of glasses with a
"main" lens and an additional "add-on" lens placed
at the bottom. The main lens corrects his vision of distant objects.
The add-on lens corrects his vision for reading.
Which of the following figures qualitatively represents the lenses in
a pair of bifocals as described above?
(a) 41.6 cm
(b) 53.9 cm
(c) 66.3 cm
(a) | P | = 1.05 diopters
(b) | P | = 1.09 diopters
(c) | P | = 1.14 diopters
(d) | P | = 1.23 diopters
(e) | P | = 1.40 diopters
A light source inside an optical fiber emits light rays with equal
intensity in all directions. The fiber has a core surrounded by a
cladding. The combination of core/cladding materials that has the
greatest transmission of light is:
(a) Plexiglass / Crown Glass
(b) Polystyrene / Fused quartz
(c) Dense flint glass / Light Flint Glass
(a) 4.5 × 108 m
(b) 6.0 × 108 m
(c) 8.0 × 108 m
(b) Fused Quartz
(a) < 10 cm.
(b) = 10 cm.
(c) > 10 cm.
Red light (l = 600 nm in air) impinges at
normal incidence on a thin plastic film (n=1.4) which is originally on
top of a thick glass plate (n=1.5).
Find t, the minimum (non-zero) thickness of the film which gives
constructive interference. (Warning: incorrect answers can be obtained
from the numbers in the problem.)
(a) t = 100 nm
(b) t = 107 nm
(c) t = 200 nm
(d) t = 214 nm
(e) t = 300 nm
(a) remain the same.
(b) change to the opposite choice.
Blue light with wavelength l = 380 ×
10-9 m is incident upon two narrow slits separated by a
distance d before striking a screen 5.2 meters away. The
distance between the central bright fringe and first dark fringe is
1.8 × 10-3 m. Calculate d the spacing between the
slits. You may approximate sin(q) » tan(q) » q .
(a) d = 0.55 × 10-3 m
(b) d = 1.10 × 10-3 m
(c) d = 1.65 × 10-3 m
(d) d = 2.20 × 10-3 m
(e) d = 4.40 × 10-3 m
(a) y < 1.8 mm
(b) y = 1.8 mm
(c) y > 1.8 mm