PHYS2220 Group challenge #3
Traveling wave
1. Consider the displacement of wave D( x, t )
1
. All values are in SI unit.
1 ( x 2t )2
(a) In which direction does this wave propagate?
x axis. (The displacement is function of x+vt.)
(b) What is the wave sp
PHYS2220 Group challenge #12
The end of classical physics
1. What is the evidence by which we know that an electron from an iron atom is identical to an
electron from a copper atom?
e
same
m
2. Rutherford studied alpha particles using the crossed field t
Exam 2 (PHYS 2220)
Name:
1. One pianist plays a note of 500 Hz while a second plays a note of 502 Hz. You will hear a
sound of frequency ( ). The sound of frequency fluctuates between loud and soft with a
frequency of ( ).
A
500 Hz, 2 Hz
B
502 Hz, 2 Hz
C
4. Two particlesparticle A and particle Bare traveling at high speeds relative to c.
Particle A has 1/2 the rest mass of particle B, and has twice the speed of particle B. Which
particle, if either, has the greater momentum?
A
3
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PHYS 222 Group Challenge #1
Relativity
Cat kn era IA 114 e
Clocks C I and C2 in frame S are synchronized. Clock C' moves at speed v relative to
frame S. Clocks C' and Cl read exactly the
Group Challenge #14
1d Quantum Mechanics
1. Consider the model potential and energy level diagram of a neutron in a nucleus below.
5
/1/1eV
fri x_v
lo
15 MeV
50 friet(


A)
How many possibilities are there for an emission of a gammaray photon?
B) Sk
Group Challenge #13
Wave Functions II and Uncertainty
1. The figure shows the wave function of electrons arriving on a screen along the xaxis.
Draw a graph of itif(x)1 2
Draw a dot pattern showing the likely distribution of
the first 50ish electrons to a
je7
PHYS 222 Exam #1
Thursday, 09/18/2008
You are allowed your 1 sided page of 8.5" x 11" notes (no worked problems, no
photocopies)
No other texts notes or informational resources are allowed
No calculators (you should not need them)
Hand in your exam an
.5
Name
IS
 2
ev
(a merovl
53 /7/
PHYS 222 Exam #3
Tuesday, 11/25/2008
You are allowed your original 1 sided page of 8.5" x 11" notes (no worked problems,
no photocopies) plus your sheets from Exam #1 and Exam #2.
No other texts notes or informational re
5. The graph shows the light intensity on a screen behind a 0.2mm wide slit illuminated
by 500 nm light waves. Using the same horizontal scale as in the top scale, draw a graph
of the light for 250 nm light waves passing through the same slit.
Intensity
6
Group Challenge #7
Wave Optics Concepts
1. Below we see a bird's eye view of a double slit experiment. As we said in class, we
could utilize dust or smoke to view the diffraction pattern in the intervening space
between the slits and the viewing screen. I
3.
Consider the (crudely drawn) snapshot graph at t=0 of the sinusoidal wave below:
v
s
.700 riv
dad
y_CF)
k
(A)
(Ai
LCC)
ert (
rre
Aj
). Ca U
a) Write the equation of this sine wave in standard D(x,t)= A sin (kx wt + 4) form (feel free
to skip arithmeti
PHYS 222 Group Challenge #2
Traveling & Sinusoidal Wave Basics
1.
The snapshot graph of a complex wave pulse at t = 2.0 sec and traveling at 2 m/s in the x
direction is sketched below.
.2.
3 Li 5
6
1
_2

3
Sketch below the history graph for the point at
Exam 1 (PHYS 2220)
Name:
1. When Beth is at rest, the object looks square to her. Now Beth is riding a bicycle at speed 0.9c.
What does the object look like?
A increases
2. The frequency B decreases , when the wave moves from one medium to another.
C is
PHYS2220 Group challenge #17
1D Quantum mechanics
1. What is the quantum number of the particle in figure?
There are 6 antinodes > n 6
2. Rank in order, from largest to smallest, the penetration distances a to c of the wave
functions corresponding to the
PHYS2220 Group challenge #16
1D Quantum mechanics
1. A particle in a box of length L in its n = 1 state.
(a) Where is the particle most likely to be found?
1 ( x)
2
2
2
sin x p( x) 1 ( x) sin 2 x
L
L
L
L
2 2
L
sin x is max at x
L
2
L
L
The pa
PHYS2220 Group challenge #15
Wave functions & Uncertainty
1. Figure shows the probability density for photons to be detected on the xaxis.
(a) Is a photon more likely to be detected at x = 0 m or at x = 1 m? Explain.
x = 1 m. This is because probability
PHYS2220 Group challenge #8
Wave Optics
1. Figure shows the light intensity o a screen 2.5 m behind an aperture. the aperture is
illuminated with light of wavelength 600 nm.
(a) Is the aperture a single slit or a double slit? Explain.
The fringes are equa
PHYS2220 Group challenge #4
Traveling wave
1. Figure shows the wave fronts of a circular wave.
(a) What is the phase difference between points A and B?
0 (They are on the same crest)
(b) What is the phase difference between points C and D?
4 rad (They are
PHYS2220 Group challenge #5
Traveling wave
1. You are standing at x = 0 m, listening to a sound that is emitted at frequency f0. The graph of
figure shows the frequency you hear during a 4 second interval. Which of the following
describes the sound source
PHYS2220 Group challenge #9
Modern Optics & Matter Waves
1. The first order xray diffraction of monochromatic x rays from a crystal occurs at angle 1.
The crystal is then compressed, causing a slight reduction in its volume. Does 1 increase,
decrease, or
PHYS2220 Group challenge #7
Wave Optics
1. The figure shows the viewing screen in a doubleslit experiment.
A. What will happen to the fringe spacing if the wavelength of the light is decreased?
y
L
d
y
fringe spacing decreases
B. What will happen to t
PHYS2220 Group challenge #13
Quantization
1. The figure shows a typical currentversusfrequency graph for a photoelectric effect
experiment done with a potential difference is zero. On the figure, draw and label graphs for the
following situations: (In e
PHYS2220 Group challenge #2
Relativity
1. As seen by an observer on earth, rocket A moves to the right at a speed 0.5c towards rocket B
moving to the left at speed 0.3c.
Is the speed of rocket A relative to rocket B 0.8c? If not, what is the speed of rock
PHYS2220 Group challenge #1
Relativity
1. As seen by an observer on earth, rocket A moves to the right at a speed 0.5c towards rocket B
moving to the left at speed 0.3c. Both rockets fire a light beam at each other.
A. What is the speed of the beam fired
PHYS2220 Group challenge #6
Superposition
1. A standing wave is oscillating at 600 Hz on a string, as shown in the figure. What is the wave
speed?
3
sol) m = 3 (3 antinodes)
f3 600 Hz
L 60cm 0.6m
L
m
m L
3
3
2
2
2 L 2(0.6m)
2
3
0.4m (You can get this
PHYS2220 Group challenge #10
Modern Optics & Matter Waves
1. Three laser beams have wavelengths a 400 nm, b 600 nm, and c 800 nm. The power
of each laser beam is 1 W.
A. Rank in order, from largest to smallest, the photon energies Ea , Eb , and Ec in thes
PHYS2220 Group challenge #11
The end of classical physics
1. Consider the parallel capacitor below.
A. Draw arrows on the diagram indicating the electric field of capacitor.
B. An electron enters the capacitor from the right. In which direction will the e
Group Challenge #12
Wave Functions I
1. An experiment has 3 possible outcomes: A, B, and C. The probability of A is 20% and the
probability of B is 30%.
What is the probability that the outcome is NOT B?
70 96
What is the probability that the outcome is e