Kingdom of Saudi Arabia
Ministry of Higher Education
Majmaah University
Vice rectorate for Academic Affairs
Measurement & Assessments Administration
The MidTerm Exam of the Second Semester 1435 / 1436 H
College of Science in Zulfi
Program: B. Sc
Course Name: Electromagnetism 2
Course Code: 322
Level: L5, 6
Date: 21/05/1436
Duration: 1 hour
The student's name: …………………………………………….
University ID:…………………………………………………….
Number of pages: 3
Examination Guidelines
1- Type your name and university identification number clearly in the space provided.
2- Use blue or black pen in answer and pencil in drawing.
3- Books or notes, papers and publications are not allowed into the examination room.
4- Students are not allowed to get out from the examination room before passing 30
minutes from the beginning of test starting.
Learning Outcomes
Communication,
Interpersonal skills
The Knowledge
information
Psychomotor
Cognitive skills
and taking
Skills
technology and
skills
responsibility
numerical skills
a
b
c
d
e
Grades
Learning
Faculty member
Corrector 1
Corrector 2
Question
outcome
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1
/……………. /……………. ………………..
Review Committee
/……………. /……………. ………………..
2
Name
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3
/……………. /……………. ………………..
4
/……………. /……………. ………………..
5
Signature
Final grade...…../….......
/……………. /…………….
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Kingdom of Saudi Arabia
Ministry of Higher Education
Majmaah University
Vice rectorate for Academic Affairs
Measurement & Assessments Administration
Exercise 1 (6 Marks)
Circle the correct answers:
1) The relation between the electric field and the electric force is given by:



 F
F
a)   q
b) E 
c) F  q E
q
E
2) The microscopic Ohm's law is given by:


a) E   j

j
c)   
E


b) j   E
3) The electric force between two charges Q1 and Q2 is equal to:
r2
a) F  K
q1 q 2
b) F  K
q1  q2
r2
4) The Lorentz force is equal to:


  
 
a) F  q v  B
b) F  q E  v  B

c) F  K

q1 q2
r2


c) F  q E
Exercise 2 (7 Marks) Gauss's law
Consider a solid sphere of radius R with a uniform charge  .
1) Write the Gauss's law
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2) Using Gauss's law Show that the magnitude of the electric field in a point M is
equal to:
2

r
 R3
a- E 
outside
the
sphere.
(
Q


d



d

sin

d

r 2 dr )
enc




2
3 0r
 0
 0
r 0
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Kingdom of Saudi Arabia
Ministry of Higher Education
Majmaah University
Vice rectorate for Academic Affairs
Measurement & Assessments Administration
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r
inside the sphere.
3 0
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b- E 
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3) Draw the graph which represents the variation of the electric field E as function
of the distance r
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Exercise 2 (7 Marks) Ampere's law
Consider an infinite cylinder of radius R with a uniform current distribution j v (in
volume).
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Kingdom of Saudi Arabia
Ministry of Higher Education
Majmaah University
Vice rectorate for Academic Affairs
Measurement & Assessments Administration
1) Using Ampere's, law Show that the magnitude of the magnetic field in a point M is
equal to:
a- B (r) 
 
0 I
outside the cylinder, where I is the total current ( I   j ds )
2 r
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0 I
r inside the cylinder.
2  R2
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b- B (r) 
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2) Draw the graph which represents the variation of the magnetic field B as
function of the distance r
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