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 131.
The exam period was 90 minutes; the mean score was 100.3; the median was
103. 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.
An electromagnetic microwave of wavelength 1.5 ×
10-6 m travels in vacuum as shown below. The electric field
has a maximum value of Emax = 80 N/C.
What is the frequency ν of the wave?
(a) ν = 2 × 1014 Hz
(b) ν = 7.5 × 106 Hz
(c) ν = 250 Hz
(a) I = 3.2 × 10-6 W/m2
(b) I = 6.5 × 10-4 W/m2
(c) I = 9.7 × 10-2 W/m2
(d) I = 8.5 W/m2
(e) I = 1.7 × 102 W/m2
(a) E and B constant in space, polarized along the z-direction
(b) E and B varying in space in the same manner, polarized along the y-direction
(c) traveling along the y-direction, E and B varying in space in the same manner
(d) traveling along the y-direction, E and B constant in space
(e) traveling along the z-direction, polarized along the y-direction
(a) Brms = 1.9 × 10-7 T
(b) Brms = 6.2 × 10-3 T
(c) Brms = 3.5 T
Consider a concave mirror having a focus f and center
of curvature C as shown below. The mirror has a radius of
curvature of R = 10 cm.
A real image is formed at a distance of 15 cm in front of the mirror.
Where is the object placed for this image? The object is placed
(a) 3 cm behind the mirror.
(b) 7.5 cm behind the mirror.
(c) 3 cm in front of the mirror.
(d) 7.5 cm in front of the mirror.
(e) 10 cm in front of the mirror.
(a) between the mirror and f.
(b) between f and C.
(c) just outside C.
(d) very far away.
(e) Such a situation could not exist.
A beam of blue light (λ = 400 nm) is incident on a pool
of water (n = 1.33). There is a thin film of oil (n =
1.5) on top of the water. The light is incident normal to the surface.
The angles are exaggerated for clarity.
What is the minimum thickness of the film which will result in
constructive interference? You can assume that the gas above the film
is air (n = 1.0).
(a) 66.7 nm
(b) 133.3 nm
(c) 153.8 nm
(d) 200.0 nm
(e) 400.0 nm
(a) constructive interference.
(b) destructive interference.
(a) λ = 321 nm
(b) λ = 428 nm
(c) λ = 573 nm
(d) λ = 649 nm
(e) λ = 725 nm
(a) vimage = 3 m/s
(b) vimage = 6 m/s
(c) vimage = 13 m/s
(d) vimage = 16 m/s
(e) vimage = 23 m/s
An ultra-fast vehicle from outer space emits yellow light of
wavelength λ = 556 nm. It comes to earth and passes you
by at one-hundredth the speed of light (c/100).
Once the vehicle has passed you and is traveling away from you, the
wavelength λ of light will appear to be
(a) λ = 354 nm
(b) λ = 562 nm
(c) λ = 731 nm
(a) λ' is shorter than λe.
(b) λ' is longer than λe.
(c) λ' is equal to λe.
(a) P = -11.7
(b) P = -5.00
(c) P = +1.50
(d) P = +5.00
(e) P = +11.7
(a) s = 1.41 mm
(b) s = 1.54 mm
(c) s = 1.91 mm
(d) s = 3.21 mm
(e) s = 7.98 mm
(a) 0.27 cm.
(b) 0.48 cm.
(c) 0.93 cm.
(d) 1.68 cm.
(e) 2.13 cm.
(a) vradio / vvisual = 1.1 × 10-11
(b) vradio / vvisual = 3.3 × 10-6
(c) vradio / vvisual = 1
(d) vradio / vvisual = 3.0 × 105
(e) vradio / vvisual = 9.0 × 1010
(a) I = 25 W/m2
(b) I = 19 W/m2
(c) I = 13 W/m2
(d) I = 10 W/m2
(e) I = 0 W/m2
An experimental physicist at UIUC measures the frequency of a laser
by performing a double-slit experiment as shown above. She places a
screen a distance L = 2 m away from the double slit. The slit
separation is 0.35 mm. If she sees the first bright fringe at point
P, 6.1 mm above central axis, what is the frequency of the laser?
The frequency is:
(a) 1.2 × 1010 Hz
(b) 9.9 × 1012 Hz
(c) 2.8 × 1014 Hz
(d) 7.8 × 1014 Hz
(e) 9.1 × 1015 Hz
(a) The bright fringes would be in the same places.
(b) The bright fringes would move farther apart.
(c) The bright fringes would move closer together.
What is the highest order diffraction fringe that can be
(a) m = 3
(b) m = 6
(c) m = 9
(d) m = 12
(e) The information is insufficient to determine the order.
Which statement on the index of refraction of the glass for red and
green light is correct?
(a) nred > ngreen
(b) nred = ngreen
(c) nred < ngreen
(a) θ = 38.2°
(b) θ = 45.0°
(c) θ = 49.2°
(d) θ = 67.6°
(e) θ = 77.8°
Where is the image from lens 1 formed relative to its center?
(a) 3 cm
(b) 7.5 cm
(c) 10 cm
(d) 12 cm
(e) 15 cm
Unpolarized light of intensity I0 is incident on
two linear polarizers, as shown below. Polarizer 1 has a vertical
transmission axis, and polarizer 2 has a transmission axis which makes
an angle of 60° with the vertical.
What fraction of the intensity I0 is transmitted
through the second polarizer?
(a) Ifinal = 0.125 × I0
(b) Ifinal = 0.25 × I0
(c) Ifinal = 0.5 × I0
(d) Ifinal = 0.75 × I0
(e) Ifinal = I0
(b) the same intensity.