Physics 172 Exam 3 Spring 2015
Name:
Remember to always: show all of your work, explain your reasoning, justify your answers,
include units, and appropriate signicant figpres to obtain full credit.
1) (10 points) Equal but opposite charges Q are placed o
Solutions to HW2 problems
What are the strength and direction of the electric field at the position indicated by the dot in the figure?
Specify the direction as an angle above or below horizontal.
Model: The electric field at the point is found by superpo
Physics 172
Review 5 Additional Problems
Spring 2015
These are problems from Chapters 33 and 34, which is the material we covered after Exam
4. For additional practice from previous chapters, work on level II and III problems from
the textbook. The soluti
Topics for Final Exam
Chapters 25 through 34 from the textbook
Tuesday June 9, 2015 (11:45 AM - 2:00 PM)
Closed book, no notes allowed.
A calculator is allowed.
Equations and constants that you will be given during the exam:
K q1 q2
F=
r2
Q
=
L
p = qs
=
Solutions to HW5 problems
What are the magnitude and direction of the electric field at the dot?
Model: The electric field is perpendicular to the equipotential lines and points downhill.
Visualize: Three equipotential surfaces at potentials of 200 V, 0 V
Solutions to HW6 problems
1.0 1020 electrons flow through a cross section of a 2.0-mm-diamtere iron wire in 5.0 s. What is the electron
drift speed?
Solve: The wires cross-sectional area is A = 103 m) 2 = 106 m 2 , and the electron current through
r 2 (1
Physics 172
Exam 1
Spring 2015
Name: _
Remember to always: show all of your work, explain your reasoning, justify your answers,
include units, and appropriate significant figures to obtain full credit.
1) (15 points) After rubbing your hair briskly with a
Solutions to HW3 problems
What is the net electric flux through the cylinder?
Visualize: Please
refer
to
the
figure.
For
any
closed
surface
that
encloses
a
total
charge
Qin , the
net electric flux through the closed surface is e = in /e0 . The cylinder en
Solutions to HW1 problems.
What is the net electric force on charge B?
Model: Charges A, B, and C are point charges.
Visualize: Please refer to Figure.
Solve: The force on B from charge A is directed downward since two negative charges repel. Coulombs law
Solutions to HW4 problems
The electric field strength is 20,000 N/C inside a parallel-plate capacitor with a 1.0 mm spacing. An electron
is released from rest at the negative plate. What is the electrons speed when it reaches the positive plate?
Model: Th
Solutions to HW7 problems
The switch in the figure has been in position a for a long time. It is changed to position b at t = 0 s. What are
the charge Q on the capacitor and the current I through the resistor (a) immediately after the switch is closed?
(b
Physics 172 Exam 4 Spring 2015
I Name: JQLw.
Remember to always: show all of your work, explain your reasoning, justify your answers,
include units, and appropriate signicant gures to obtain full credit.
1) (10 points) An electron moves with a speed of 8.
Solutions to HW9 problems
The figure shows a 2.0-cm-diameter solenoid passing through the center of a 6.0-cm-diameter loop. The
magnetic field inside the solenoid is 0.20 T. What is the magnetic flux through the loop when it is
perpendicular to the soleno
Solutions to HW 10 problems
At t = 0 s, the current in the circuit in the figure is I0. At what time is the current 1/2 I0?
Visualize: This is a simple LR circuit if the two resistors in series are treated as an equivalent resistor in series with the
indu
Solutions to HW8 problems
What is the line integral of B B between points i and f in the figure?
Model: The magnetic field is that of a current flowing into the plane of the paper. The current-carrying wire is very long.
Solve: Divide the line integral in
Physics 172 Exam 2 Spring 2015
,7 Km
Name: 77"
Remember to always: show all of your work, explain your reasoning, justify your answers,
include units,I and appropriate significant gures to obtain full credit.
1) (15 points) Use Gausss Law to derive the el
Physics 172
Review 1 (Ch 25-26)
Spring 2015
Skills and information you should know from previous courses
Vector addition and subtraction.
Calculation of x and y components for vectors.
Cross product of two vectors.
Calculation of sin , cos , tan where is
Physics 172
Review 3 Additional Problems
Spring 2015
(1) The graph shows the electric potential as a function of x. Draw the graph of Ex versus x in
this same region of space. Include an appropriate scale on the vertical axis.
(2) For each contour map:
i.
Physics 172
Review 2 Additional Problems
Spring 2015
(1) Use Gausss law to derive the electric field outside a uniformly charged sphere of radius R.
Use a Gaussian surface, in this case a sphere of radius r, this radius is going to be larger than the
radi
Readings for PHY 172, Spring 2015
This file will be updated throughout the quarter. You must check it often for updates.
The warm-up quizzes are due by 8 AM every Monday and Wednesday in Mastering Physics
(except for week 1, when the first warm-up quiz is
Physics 172
Review 4 Additional Problems
Spring 2015
(1) The graph shows the voltage as a function of time on a capacitor as it is discharged
(separately) through three different resistors. Rank in order, from largest to smallest, the values
of the resist