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 127.
The exam period was 90 minutes; the mean score was 94.0; the median was
98. Click here to see page1
page3 of the formula sheet that came
with the exam.
Some helpful information:
• A reminder about prefixes: p (pico) = 10-12; n (nano) =
10-9; μ (micro) = 10-6; m (milli) =
10-3; k (kilo) = 10+3; M or Meg (mega) =
10+6; G or Gig (giga) = 10+9.
A message is sent via radio wave (λ = 10 m) from Earth
to a nearby star, Proxima Centauri, which lies 1.3 parsecs from Earth.
A parsec is a unit of length and 1 parsec = 3.1 × 1016
m. How long will it take the message to reach Proxima Centauri traveling
(a) 0 yrs, the message arrives instantly.
(b) 1.38 yrs
(c) 4.26 yrs
(d) 255.0 yrs
(e) 1.38 × 108 yrs
(a) take less time to reach its destination.
(b) arrive at its destination in the same amount of time.
(c) take longer to reach its destination.
Unpolarized light with intensity I0 travels through
a linear polarizer whose transmission axis forms a 45° angle with
respect to the vertical. The light then travels through another
polarizer whose transmission axis makes a 33° angle with respect to
the previous polarizer. What is ratio of the final intensity
I2 of the light relative to its initial intensity
(a) I2 / I0 = 0.35
(b) I2 / I0 = 0.43
(c) I2 / I0 = 0.50
(d) I2 / I0 = 0.72
(e) I2 / I0 = 1.00
(a) I2' < I2
(b) I2' = I2
(c) I2' > I2
(a) 0.95 J/m3
(b) 1.30 J/m3
(c) 1.43 J/m3
(d) 1.88 J/m3
(e) 2.44 J/m3
The light-emitting car speeds up.
A detector in car B notices the emitted light
(a) shifts to longer wavelength.
(b) shifts to shorter wavelength.
(c) remains unchanged.
Ignore any reflections at the air-water interface and assume the
light travels exactly perpendicularly to the surface of the Earth. The
index of refraction of water n = 1.33.
(a) 20 ns
(b) 24 ns
(c) 40 ns
(d) 48 ns
(e) 53 ns
What is the ratio of the final electric field E2 to
the initial electric field E0?
(a) E2 / E0 = 0.00
(b) E2 / E0 = 0.01
(c) E2 / E0 = 0.10
(d) E2 / E0 = 0.60
(e) E2 / E0 = 0.95
Light, an electromagnetic wave, leaves a distant star. The light
from this star enters the Earth's atmosphere, which has a refractive
index n = 1.0003.
Which of the following of the properties of light does not
change during this transition?
(a) at a location beyond c, the center of curvature
(b) These rays will never converge.
(c) half the focal point, f/2
(d) between half the focal point and the focal point
(e) the focal point, f
An object is placed 1 cm from a concave mirror of focal length
f = 2 cm as shown along the principle axis.
Where is the image formed in the system?
(a) 10 cm in front of the mirror
(b) 3.33 cm behind the mirror
(c) 2.0 cm behind the mirror
(d) 3.33 cm in front of the mirror
(e) infinitely far in front of the mirror
(a) real and upright.
(b) virtual and upright.
(c) virtual and inverted.
(a) to the left of the focus
(b) to the right of the focus
(a) P = 6.67
(b) P = 3.33
(c) P = 2.00
(d) P = -3.33
(e) P = -6.67
A diverging lens and a concave mirror are positioned as
shown in the diagram. The object is placed 7 cm to the left of the
lens. The lens and the mirror are 18 cm apart.
Where is the final image located?
(a) 2.44 cm to the right of the lens
(b) 4.12 cm to the left of the lens
(c) 7.13 cm to the left of the lens
(d) 9.77 cm to the right of the lens
(e) 15.56 cm to the right of the lens
(a) m = 0.60
(b) m = 0.71
(c) m = 1.40
(d) m = 1.67
(e) m = 2.50
A mercury-vapor lamp produces two strong emission lines in the green
segment of visible light. The two wavelengths are 546.1 nm and 578.2
nm. Light from the lamp shines through a diffraction grating containing
slits with separation 15 μm onto a screen 2 meters away.
What is the distance between the first-order maximum corresponding to
546.1 nm and the first-order maximum corresponding to 578.2 nm?
(a) 4.3 mm
(b) 5.1 mm
(c) 6.3 mm
(d) 7.4 mm
(e) 9.2 mm
(a) They will be closer to the center of the screen.
(b) They will be farther away from the center of the screen.
(c) Their positions will not change.
If the thickness of the anti-reflective coating is 74.6 nm, what is
the wavelength in air of the light that will be eliminated by the
(a) 320 nm
(b) 412 nm
(c) 560 nm
(d) 732 nm
(e) 824 nm
What is the interplanar spacing d ?
(a) 0.039 nm
(b) 0.36 nm
(c) 0.75 nm
(d) 0.98 nm
(e) 1.5 nm
Which is the first frequency above 1 kHz that will not be picked up by
the microphone? The speed of sound is 343 m/s.
(a) 3.40 kHz
(b) 3.05 kHz
(c) 2.55 kHz
(d) 1.50 kHz
(e) All frequencies above 1 kHz will be picked up.
(a) purple = 400 nm
(b) red = 600 nm
(c) yellow = 580 nm
(a) θred / θblue = 1.50
(b) θred / θblue = 1.24
(c) θred / θblue = 1.07
(a) ray 1
(b) ray 2
(c) ray 3