Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Fall 2009 Exam 1 for CPHY 122: Physics Problems, Exams of Physics

The instructions and problems for the fall 2009 exam 1 of the cphy 122: physics course taught by h. L. Neal. The exam covers topics such as quarks, electric forces, electric fields, and charged shells.

Typology: Exams

Pre 2010

Uploaded on 08/04/2009

koofers-user-xqf
koofers-user-xqf 🇺🇸

10 documents

1 / 2

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
CPHY 122
Fall 2009 Exam 1
Instructor: H. L. Neal
February 6, 2009
INSTRUCTIONS: (1) Work all of the problems below. (2) Do not put more than one
problem on a single sheet of paper. (3) Write neatly and legibly in dark ink. (4) No cheating
or collaboration of any kind is allowed on exams. All questions must be directed to me by
E-mail or at phone (404-577-9007, anytime after 5 PM and before 1 AM). (5) .The exam is
due promptly at the start of class on Wednesday, February 11. HAPPY LEARNING!
PROBLEMS
1. Protons and neutrons are made from combinations of the two most common quarks,
the d(or down) quark and the u(or up) quark. The dquark has a charge of 1
3eand
the uquark has a charge of +2
3e. How could three of these quarks combine to make
(a) proton and (b) a neutron?
2. Draw an equilateral triangle with sides of length L. Label each of the three vertices with
the numbers 1, 2, and 3, respectively. At the three vertices place three point charges as
follows: qat 1, qat 2, and qat 3. (a) What is the total electric force on the charge at
vertex labeled 1? (b) If two of the charges form an electric dipole moment, what is the
electric dipole moment (vector)? (c) What is the torque on the electric dipole moment
due to the electric eld of the third charge?
3. What is the electric ux through the hemispherical open surface of radius Rshown
below?
E
α
Created usi ng UNREGISTERED Top Dr aw 3.10 Feb 7, '108 8:58:51 AM
The uniform electric eld E is at an angle relative to the horizontal.
4. A point charge Qis xed at the center of a uncharged spherical conducting shell of
inner radius aand outer radius b. What is the induced surface charge densities on the
(a) inner and (b) outer surfaces?
1
pf2

Partial preview of the text

Download Fall 2009 Exam 1 for CPHY 122: Physics Problems and more Exams Physics in PDF only on Docsity!

CPHY 122

Fall 2009 Exam 1

Instructor: H. L. Neal

February 6, 2009

INSTRUCTIONS: (1) Work all of the problems below. (2) Do not put more than one problem on a single sheet of paper. (3) Write neatly and legibly in dark ink. (4) No cheating or collaboration of any kind is allowed on exams. All questions must be directed to me by E-mail or at phone (404-577-9007, anytime after 5 PM and before 1 AM). (5) .The exam is due promptly at the start of class on Wednesday, February 11. HAPPY LEARNING!

PROBLEMS

  1. Protons and neutrons are made from combinations of the two most common quarks, the d (or down) quark and the u (or up) quark. The d quark has a charge of ^13 e and the u quark has a charge of +^23 e. How could three of these quarks combine to make (a) proton and (b) a neutron?
  2. Draw an equilateral triangle with sides of length L. Label each of the three vertices with the numbers 1, 2, and 3, respectively. At the three vertices place three point charges as follows: q at 1, q at 2, and q at 3. (a) What is the total electric force on the charge at vertex labeled 1? (b) If two of the charges form an electric dipole moment, what is the electric dipole moment (vector)? (c) What is the torque on the electric dipole moment due to the electric Öeld of the third charge?
  3. What is the electric áux through the hemispherical open surface of radius R shown below?

E α

Created using UNREGISTERED Top Draw 3.10 Feb 7,'108 8:58:51 AM The uniform electric Öeld E is at an angle relative to the horizontal.

  1. A point charge Q is Öxed at the center of a uncharged spherical conducting shell of inner radius a and outer radius b. What is the induced surface charge densities on the (a) inner and (b) outer surfaces?
  1. Consider a ring of charge of radius a, linear charge density  = , and total charge Q, where  is angle between the source vector and the x axis. (a) Find the total charge Q in term of the constant a? (b) What is the electric Öeld at any point along the axis of the ring?
  2. A charge distribution has the shape of a very long thin cylindrical shell of length w, radius a, and total charge Q. What is the electric Öeld at any point (a) inside and (b) outside the shell?
  3. An inÖnite sheet of charge has a circular hole of radius a. What is the electric Öeld at any point along the axis of the hole? [HINT: Use the superposition principle and the results of problem 20.69]
  4. Any three problems at the end chapter 22.