Homework # 3 (Due 9.18.12 in class)
PHY 355: Modern Physics
This homework assignment should be turned in at the beginning of class sharp. You may
work in groups but you are each asked to submit your own solutions to the problems.
1. Suppose that the veloc
doyle (dwd596) HW02 web manual markert (58195)
This print-out should have 17 questions.
Multiple-choice questions may continue on
the next column or page nd all choices
before answering.
The last two (manual) questions need to be
handed in via paper on Tu
doyle (dwd596) HW03 web manual markert (58195)
This print-out should have 18 questions.
Multiple-choice questions may continue on
the next column or page nd all choices
before answering.
001 10.0 points
A space vehicle is moving at a speed of 0.541 c
with
PHY355: Modern Physics
Fall 2013
Class Meetings: Unique number 59215 (T-Th 11:00 am - 12:30 pm) WEL 2.122
Instructor: Sacha Kopp, Associate Dean, College of Natural Sciences
(WCH 2.222, 471-0461) - Oce hours: Thu 3-4pm or by appt.
Please email me at kopp@
Homework 2 Solutions: Phy 355, Fall 2016
Tyler Guglielmo
September 2016
1.
(a) The pulses have a period of 0 in the ship frame, and occur at the same point in space,
(x0 , t0 ) = (0, 0 ). Lets transform to the station frame using Lorentz transformations:
PHY355
Homework 9
November 11, 2016
(1) A wave/particle of mass m approaches a barrier of width L, and height
V0 = 4h2 /(mL2 ). Make a plot of the transmission (T ) as a function of the
particle energy E expressed as a fraction of V0 (that is, plot versus
PHY355
Homework 8
November 4, 2016
(1) A particle in a one-dimensional box is confined to the region [ L2 , + L2 ].
Calculate the probability of finding the particle near the edge of the box, say
in the sub-region [ L2 , 3L
8 ] as a function of quantum nu
Homework 7 Solutions: Phy 355, Fall 2016
Tyler Guglielmo
October 21, 2016
1. For the longest wavelength, we need to see the energy difference between the first and second
excited states (n = 2 n = 3). The energy levels of a basic hydrogen atom are given b
PHY355
Homework 1
August 26, 2016
(1) Two inertial coordinate systems S and S 0 are moving with respect to
each other at c/2. Draw a Minkowski diagram relating these two systems.
(a) Draw the hyperbola x2 (ct)2 = 1 on your graph. (b) At what value
of x do
Homework 6 Solutions: Phy 355, Fall 2016
Tyler Guglielmo
October 14, 2016
1.
(a) The hyperfine transition is the transition between hyperfine split levels in the ground
state of hydrogen. There are two levels here and the energy differences are 5.8 eV.
Th
Homework 8 Solutions: Phy 355, Fall 2016
Tyler Guglielmo
November 12, 2016
1. We begin by solving the Schrodinger equation (SE) for a one dimensional infinite square well
centered on the origin. The SE equation for this problem is given by (note that the
Homework 3 Solutions: Phy 355, Fall 2016
Tyler Guglielmo
September 16, 2016
1.
(a) Radiation pressure is given by Prad = Ef lux /c. The correct equation to use would be
Prad = 2Ef lux /c, but I will accept both solutions. Thus,
Prad =
1 kW/1 m2
3.33 106
Version 025 Exam2 markert (58195)
This print-out should have 12 questions.
Multiple-choice questions may continue on
the next column or page nd all choices
before answering.
The manual questions will count for 20
points each
1
6. 1.68
7. 0.8
8. -0.9
9. 0.
Version 112 Exam1 markert (58195)
This print-out should have 14 questions.
Multiple-choice questions may continue on
the next column or page nd all choices
before answering.
2 manual questions are in the back of the
exam: Question 13 and 14
001 10.0 point
doyle (dwd596) HW09 web manual markert (58195)
1
This print-out should have 18 questions.
Multiple-choice questions may continue on
the next column or page nd all choices
before answering.
001
10.0 points
003
10.0 points
What is the approximate ratio of t
Welcome to Modern Physics
Trails of droplets of condensation formed by ionizing charged particles passing through a cloud chamber.
The scientific revolutions in fields of physics have deeply impacted the way we think about space, matter,
energy, and our p
Practice Problems
Wave/Particle Duality Problems
1. To what voltages must we accelerate electrons (as in an electron microscope, for example) if we wish
to resolve a virus of diameter 12 nm? An atom of diameter 0.12 nm? A proton of diameter 1.2 fm?
2. A f
doyle (dwd596) HW01 web markert (58195)
This print-out should have 12 questions.
Multiple-choice questions may continue on
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before answering.
001 10.0 points
Are any leptons made of quarks?
1. None of these
2. No;
cha
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1
(2.99792 108 m/s)2
This print-out should have 17 questions.
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before answering.
1
1 (0.78)2
1
= 8.98971 1011 J .
001 (part 1 o
doyle (dwd596) HW06 web manual markert (58195)
1
This print-out should have 14 questions.
Multiple-choice questions may continue on
the next column or page nd all choices
before answering.
003 10.0 points
If the momentum of an electron doubles, by
what fa
doyle (dwd596) HW05 web manual markert (58195)
This print-out should have 19 questions.
Multiple-choice questions may continue on
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before answering.
1
Which light?
1. common blue light
2. very bright red light correct
doyle (dwd596) HW07 web manual markert (58195)
This print-out should have 15 questions.
Multiple-choice questions may continue on
the next column or page nd all choices
before answering.
001 (part 1 of 4) 10.0 points
Find the energy of the ground state (n
doyle (dwd596) HW08 web manual markert (58195)
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001 10.0 points
An electron is conned to a potential well
which spans
Homework 4 Solutions: Phy 355, Fall 2016
Tyler Guglielmo
September 24, 2016
1. The probability of getting k ones after n rolls is given by the binomial distribution
k nk
5
n
1
P (k) =
6
6
k
(1)
So, if we want to have 0 ones after 20 rolls,
P (0) =
520
.
choi (jwc2728) HW09 markert (56910)
This print-out should have 19 questions.
= 18 1
Multiple-choice questions may continue on
= (3 2) (i) = 3 2i.
the next column or page find all choices
before answering.
001 (part 1 of 6) 10.0 points
First I want us to g
1 When you put metal in a microwave oven, it ejects electrons. Is this due to the photoelectric
eect? Why or why not? As a reference, the work function of iron is 4.7 eV.
The kinetic energy of photoelectrons is given by the dierence between the photons en
quick study
The measurement Einstein
deemed impossible
Mark G. Raizen and Tongcang Li
Particles undergoing Brownian motion
move with constant velocity between
Brownian kicks. Albert Einstein predicted
the velocity distribution. but he wrongly
thought hi