1: D
2: B
3: E
4: B
5: C
6: A
7: D
8: E
9: B
10: E
11: A
12: A
13: D
14: A
15: C
16: A
17: C
18: A
19: C
20: B
21: A
22: E
23: C
24: E
25: D
26: D
27: D
28: C
29: E
30: B
31: E
32: C
33: C
CU-Prime Talks for Undergraduates
Manipulating
Atoms and
Molecules
Manipulating
Atoms
and
Molecules
UltrafastLaser
Laser Pulses
with with
Ultrafast
Pulses
by Chris Mancuso
By Chris Mancuso
Tuesday, March 31st at 5:00 p.m.
Gamow
Tower,
11th Floor
Room
Tues
A strategy for using Amperes Law:
1. Use symmetry. 2. Draw a useful loop.
3. Calculate Ienc. 4. Call B B, calculate loop
integral. 5. Plug 3 and 4 into Amperes Law
and solve for B.
Yesterday: B-field inside a wire. Today:
(i) the field from an infinite cu
Faraday 33
A solenoid has an increasing current causing an
increasing B-field in its interior. An end-on view of
the solenoid is shown below. An electron is directly
below the solenoid. While the current I in the solenoid
is increasing, what is the direct
Midterm Exam #3 on Thursday 4/9 at 7:30. There is no
make-up.
Medical excuses will require a doctors note. Go
to same room you went to last time.
Pro tip: Do your CAPA homework before the exam
(ie, do it two days early.) Do the tutorial
HW you get assigne
Faraday 22
There are two loops of wire. The red loop has
an increasing current. What is the direction of
the force on right side of the blue wire?
X
F
A:
B:
C:
D:
E: No net force.
Faraday 23
There are two loops of wire. The red loop has an
increasing cu
Right hand rule #1:
cross-product of two
vectors:
c=axb
second vector
(B or B or F)
cross-product
(F or F or t)
Examples:
F =qvxB
F=I l xB
t = rxF
first vector
(v or l or r)
Current
Right hand rule #2:
Something wraps around an axis: torque
causes an acce
Electrical generator (750 MW)
Faraday 15
What is the direction of the magnetic
force on an electron in the wire?
v
X X
A: up
B: down
B
C: right
D: left
E: The force is zero.
X
X X X
Faraday 24
How do the charges separate inside the
copper bar as it is mov
Midterm exam average 69, sigma 15. Youll get your
booklet back at tutorial.
1.Look your exam over and understand the solutions.
2.If you still have questions about the score on your
exam, you should:
1. Write your question on a separate piece of
paper.
2.
Magnet 8
A + particle is released from rest in a
region where there is a constant,
uniform, E-field and a B-field (shown
below).
Which path will the positive particle
follow? (Paths shown are in plane of
page.)
E
A B C
D: will not move
E: other
B(out)
Mag
Magnet 29
What is the magnitude dB at
the center of a current loop?
A) Zero
B)
C)
0 dl
I
4 R
0 dl
I 2
4 R
D)
E)
0 dl
I 3
4 R
0
dl
I
4 (2 R) 2
Magnet 24
What is the direction of the B- Field at
point P?
A:
B:
C: 0
D:
E: Other
Magnet 25
Which point, A or B
CU-Prime Talks for Undergraduates
Big Game Hunting in SaturnsRings
by Morgan Rehnberg
FR
EE
PIZ
ZA
Tuesday, March 3rd at 5:00 p.m.
Gamow Tower, 11th oor Commons Room
The rings of Saturn are among the most beautiful natural objects yet discovered,
but thei
CU-Prime Talks for Undergraduates
Nanodiamonds:
Optical Sensing of Nuclear Spins
by Molly May
2 carat diamond
FR
EE
PIZ
ZA
.000000000000000001 carat diamond
Tuesday, March 17th at 5:00 p.m.
Gamow Tower, 11th oor Commons Room
do with
a 0.000000000000000001
Exam: tomorrow.
.
Inductor 100
Solenoid #1
Solenoid #2
Current such that B=B1 Current such that B2=4B1
Length d2 = d1/2
Length d = d1
Cross-section A2 = A1/2
Cross-section A = A1
Stored energy
E2/E1=
E1
Stored energy E2
A. B. C. 1 D. 2 E. 4
AC circuits 1
Encyclopedia Brittanica
AC circuits 5
An electrical engineer at a power plant wants to
reduce the energy wasted during power
transmission from the plant to the city. The
power output Po=IV of the plant is fixed at 100
MW. The engineer decides to double Vo
The practice exams that are posted in this folder are actual exams that were administered in PHYS1120 a
few years ago. The style and length of our exam will be somewhat different. The answers to these
practice exams will be posted a few days before the ex
1 of 2
PHYS1120 Exam I review
Things to remember for PHYS1110:
algebra, trig (sin, cos, .)
vector math, especially vector addition
Fnet = ma problems, free-body diagrams
Ch.21 Charges and Fields
q1 q 2
r2
Coulomb's Law: F
Definition of electric field: E
E
electric field 45
Semi-infinite line of uniform charge density l:
-h
x
0
dq= l dx
Q: What is at x=0?
=
=
2
Discuss with your neighbors.
First what direction does the field point, at x=0?
Then what is magnitude of total field. How you might
set up the a
The final: multiple-choice questions only.
Will cover the same material covered on the three
mid-terms, plus:
Self-inductance. LR circuit. Energy stored in B field.
LC circuit, oscillation frequency. Transformers. AC
Power. Displacement Current in Amperes
This week: EM waves, Polarization
Next Week: Optics
Last Week: Review of entire course
Final Exam: May 5, 7:30 am. Wait, what?
On-line clicker registration form
First name _
Last name_
Student ID _
Remote ID_
On the line that says Student ID, I
should put
Clicker Question
EMwave 6
Two traveling waves 1 and 2 are described by the equations.
, =
, =
The wavelength of wave 1 is most nearly
A) 1m
B) 2m
C) 3m
D) 4m
E) Impossible to tell
t
x
y ( x, t ) A sin 2
T
Clicker Question
EMwave 5
Two traveli
Final Exam: Tuesdaty May. 5, 7:30 -10:00 a.m!
If your midterms were in Muenzinger, Chem, or Math,
same place for final. /if your midterm was in
Humanities, come to G1B30 for final.
Today and Monday: Ray optics.
Tuesday, Tutorial, highly recommended.
Wedne
E-field
EMwave 10
An electromagnetic plane wave propagates to the right. Four
antennas are labeled 1-4. The antennas are oriented
vertically. Antennas 1,2, and 3 lie in the x-y plane. Antennas
1,2, and 4 have the same x-coordinate, but antenna 4 is
locate
Final Exam: Tuesday 5 May. 7:30 a.m!
Location(s) TBA
Q: When will make-up exam be?
A: Mid-December, 2015. (possibly
end of summer session, also.)
Today: Polarization, Diffraction, Interference.
Wednesday Interference, Start of Ray Optics. FCQs!
Friday, Ne
Ray Optics (= classical optics)
Ignore diffraction. (wavelength too short to matter)
Ignore oscillations (freq. too fast to worry about.)
Assume light travels in straight lines,
Except for discrete changes in direction:
reflection.
refraction.
Optics 1
Wh
Exam tomorrow at 7:30 p.m.
For rooms, see class
website. Good luck!
You are not required to do this, but it could
be to your advantage to get tutorial homework
and CAPA homework done before the
exam, perhaps tonight.
No cell phone. Calculator recommended.
Current 32
A
switch
What happens to the
(identical) bulbs when
the switch is closed?
12 V
B
12 V
A) A glows, B changes
B) A glows, B stays same
C) A stays same, B changes
D) A stays same, B stays same
Midterm 2: Exam Thursday 7:30. Same
rooms (or see web)
Current 30
The circuit shown contains an ideal battery
with 2 identical bulbs.
IA
A
V
B
IB
When the switch is closed, what happens to the
currents through points A and B?
A) IA same, IB
B) IA , IB same
C) IA same, IB same
D) IA , IB
E) IA , IB
Current 31.
ElectricField44
In the four separate scenarios, F indicates the direction
of the force from charge Q on test charge q. E
indicates the direction of the electric field from Q
measured at the location of q. Which of the four
scenarios get the directions of