Physics 1230 – Light and Color
Final Exam – 19 December 2001
There were 4 different versions of the exam. The versions had the same
questions and answers, but the order of the answers was different in each
version. The correct answer to each question is identified by an asterisk in
the following text.
:
1
& 2: Bifocals are eye glasses whose
lenses have two different focal lengths, one for distance vision at the top of
the frame and one for reading and other close up work at the bottom.
1.
A person who wears bifocals probably has eyes that suffer from
() myopia
() hyperopia
() astigmatism
*() presbyopia
() too many cones near the top
and bottom of the eye
2. A person who wears bifocals
() always has astigmatism
() never has astigmatism
*() sometimes has astigmatism
() always has myopia
() never has myopia
3. If a person wears glasses with positive
lenses, then, that person’s eye alone
() will have a near point of less than 25 cm
*() will have a near point of greater than 25 cm
() will have a near point equal to 25 cm and a far
point of 2 m
() will have a near point equal to 25 cm and a far
point of 25 m
() will have a near point equal to 25 cm and a far
point of infinity
4. If a person wears glasses with negative
lenses, then that person’s eye alone
*() will have a near point of less
than 25 cm
() will have a near point of greater
than 25 cm
() will have a near point equal to
25 cm and a far point of 2 m
() will have a near point equal to
25 cm and a far point of 25 m
() will have a near point equal to
25 cm and a far point of infinity
5.
If a person has an eye with a near point of 50 cm and a far point of 60 cm,
then
() that person has myopia and needs
eye glasses with a positive lens
() that person has myopia and needs
eye glasses with a negative lens
() that person has hyperopia and needs
eye glasses with a positive lens
() that person has hyperopia and
needs eye glasses with a negative lens
*() that person has presbyopia and
needs bifocals
6.
An eyeglass made using only a cylinder lens would be used for
() a person whose eye has no
accommodation
() a person whose eye has
astigmatism and myopia
*() a person whose eye has
astigmatism only
() a person whose eye has
astigmatism and hyperopia
() a person whose eye has presbyopia
7. A positive lens has a focal length of 6 cm.
If that lens is used as a simple magnifier, the magnification relative to the
eye acting alone is about
() 43 and the image is erect
*() 4.3 and the image is erect
() 8.2 and the image is inverted
() 52 and the image is inverted
() 4.3 and the image is inverted
8.
A compound microscope is made using
() a long focal length positive lens
for both the objective and the eye piece
*() a short focal length positive
lens for both the objective and the eye piece
() a long focal length positive lens for the
objective and a short focal length positive lens for the eye piece
() a short focal length positive lens for the
objective and a long focal length positive lens for the eye piece
() a positive lens for the eye piece
and a negative lens for the objective
For
9 & 10: A Galilean telescope has two lenses of focal lengths +60 cm and –15
cm.
9. The separation between the two lenses
should be:
() 75 cm
() 60 cm
() 50 cm
*() 45 cm
() 30 cm
10. The magnification will be
() 5 and the image is erect
() 5 and the image is inverted
*() 4 and the image is erect
() 4 and the image is inverted
() 45 and the image is erect
For
11 & 12: An astronomical telescope has two lenses of focal lengths 60 cm
and 15 cm
11.
The separation between the two lenses should be:
*() 75 cm
() 60 cm
() 50 cm
() 45 cm
() 30 cm
12.
The magnification will be
() 5 and the image is erect
() 5 and the image is inverted
() 4 and the image is erect
*() 4 and the image is inverted
() 45 and the image is inverted
13.
The tri-stimulus values are
() the amounts of red, green and
blue needed to match any color
() the amounts of cyan, magenta and
yellow needed to match any color
() the responses of the 3 types of
cones in the eye to any color
() the values of hue, saturation and
intensity needed to match any color
*() the amounts of 3 specific
imaginary colors needed to match any color
14.
Using the tri-stimulus values, we can
*() match any color
() match any color that is not too
saturated
() match colors that are completely
saturated
() match any color except purple
hues
() match any color except for the
primaries red, green and blue
15.
Combinations of only red and blue
() produce colors that are
complementary to yellow
() produce colors that are
complementary to orange
*() produce colors that are
complementary to green
() produce colors that are
complementary to magenta
() produce colors that are
complementary to cyan
16.
The saturation of a color specifies
() its wavelength
() its brightness as perceived by
the eye
() the amount of black ink needed to
print the color
() the maximum value of the plot of
its intensity as a function of wavelength
*() the width of the plot of its intensity as a
function of wavelength
17.
The 3 subtractive primaries are
() red, blue and green
() black, white and blue
() red, white and blue
*() cyan, magenta and yellow
() cyan, blue and green
18.
The hue of a combination of two monochromatic lights with wavelengths of 590 nm
and 550 nm is
() red
*() yellow
() orange
() green
() blue
19. How much green would you use to make a light
that matches light of 580 nm?
() 5.5%
*() 55%
() 45%
() 4.5%
() 35%
20. What is the approximate complementary color
of 580 nm light?
*() 478 nm
() 488 nm
() 498 nm
() 508 nm
() 518 nm
21.
The color that is complementary to cyan is
*() red
() orange
() yellow
() green
() blue
22. The color that is complementary to green is
() red
() yellow
() blue
() orange
*() magenta
23. To print text that is to appear red when
viewed in white light, you would use
() an ink that absorbs only magenta
() an ink that absorbs only yellow
() an ink that absorbs only green
() an ink that absorbs only blue
*() an ink that absorbs only cyan
24. A filter that passes only monochromatic red
light at 650 nm is placed on top of a filter that passes only monochromatic
green light at 530 nm. When 460 nm blue light strikes one side of the pair of
filters, the light that comes out of the other side (after passing through both
filters) is
() red
() green
() blue
() yellow
*() black – no light comes out the
other side
25.
The dyes used in developing and printing subtractive color film are
() red, blue and green
() red, blue and yellow
*() cyan, yellow and magenta
() 3 different silver halides
() silver halide, metallic silver
and silver chloride
26.
If subtractive color film is used to photograph a bright blue sky, the color of
the negative will be
() dark magenta
() light magenta
() light green
*() dark orange
() light orange
27.
A coupler is used in color photography to
*() interact with the developer to produce
a dye wherever there is free silver
() interact with the developer to
produce a dye wherever there is no free silver
() produce a positive image directly
without the need for printing the negative
() maintain the balance between the
red, blue and green developers
() permit photographing saturated
colors
28. If black and white film remains in the
developer for too long, the image is spoiled because
() all of the silver halide is converted to metallic
silver and the negative turns completely white
*() all of the silver halide is converted to
metallic silver and the negative turns completely black.
() the negative turns completely clear because all
of the silver halide is dissolved in the developer and nothing remains on the
film base
() the negative turns completely dark because it
becomes coated with a layer of dried developer that is opaque
() the developed image is too dark
but is otherwise okay
29. The emulsion in black and white reversal
film
() uses couplers to reverse the image after
development
() uses couplers to reverse the image before
development
*() is the same as film that produces negatives but
the two are developed differently
() is not the same as film that produces negatives
but the two are developed the same way
() is mounted behind the substrate and is exposed
from the back side
30.
If you see two monochromatic lights which have exactly the same output powers
and whose wavelengths are 600 nm and 620 nm, then
() the intensities look the same,
but the 620 nm light looks greener
() the intensities look the same,
but the 620 nm light looks redder
() the 600 nm light looks brighter
and the colors looks the same
*() the 600 nm light looks brighter
and greener
() the 620 nm light looks brighter and redder
31.
In order to describe colors, the brain uses the psychological primary colors,
which are
() red, blue and green
*() red, blue, green and yellow
() cyan, magenta, yellow and black
() red, blue, green and white
() red, yellow and blue
32.
Light of 350 nm blue is combined with light of 750 nm red. The combination
appears
*() black
() red
() blue
() magenta
() white
33. A monochromatic light beam
() is very bright
() is very dim
() appears white
*() is completely saturated
() is completely unsaturated