Accelerated PhysicsChapter 1 Problem Set
Answer each of the following questions. Your answers need to be supported by work
and/or explanations as called for in order to earn full credit.
1.
Use factor label
Section 66, 67, 68 Mechanical Energy and its Conservation
We can distinguish between the work done by conservative forces (not dependent of path
taken) and the work done by nonconservative (dependent on path taken) forces.
We find that the work done by
Can a force be exerted on an object and no work be done on the object?
Problems solving strategies for Work
1. Draw a free body diagram.
2. Choose a convenient coordinate system. (Usually it is convenient to choose the
direction of motion).
3. Apply Newto
Section 62 Work Done by Varying Force
The work done by a varying force can be determined graphically. If you plot F vs d, then the
work is the area under the curve at the two points.
The force on an object, acting along the x axis, varies as shown above.
mine (a) the
the crate.
work done by each force acting on the crate, and (b) the net work done
(4) The work done on a backpack (a) Calculate the work a hiker must do on a backpack of
mass m = 15 kg in order to carry it up a hill of height h = 10 m, as sho
A dart of mass 0.100 kg is loaded in a toy dart gun. The spring in the gun has a spring constant
of 250 N/m. The spring is compressed 6.0 cm and then released. What speed does the dart
leave the gun with?
A 1.60 kg block slides with a speed of 0.950 m/s o
A ball of mass m = 2.60 kg, starting from rest, falls a vertical distance h = 55.0 cm before
striking a vertical coiled spring, which it compresses an amount Y = 15.0 cm. Determine the
spring constant. Assume the spring has negligible mass, and ignore air
b. How much energy did this require?
2. An elevator car of mass 1,600 kg, carries people, mass of 200 kg. A constant friction force of
4,000 N acts against the motion. Find the power needed for a motor to lift the car +
passengers at a constant velocity v
b. What was the net work done on the ball to make it reach this speed, starting from
rest?
(2) Calculate the net work required to accelerate a car, mass m = 1000kg car from v1 = 20
m/s to v2 = 30 m/s.
(3) A car traveling at speed v1 = 60 km/h can brake t
Section 61 Work done by a constant force
Work what is accomplished when a force is applied to an object to move it over a distance
The work done on an object by a constant force (constant in both magnitude and direction) is
defined to be the product of t
. 1. A wave' 15 introduced into a medium
Wave Basics KEY Name: MW._._._._
Desc1:ibing Waves
Read from :iLesson 2 of the Waves chapter at The Physics Classroom:
http: IIwww. physicsclassroom com/C111sstavesIuIDIZahtml
http :./Iwww physicsclas sroom .comIC
A
4.
D
. , . f i .
10. The period of a 261Hertz sound wave is 2% Ian;
Wave Basics
l
7. Olive Udadi accompanies her father to the. park for an afternoon of fun. While ther. .7 . a *
swinIg and begins a motion characterized by a complete backandforth c
The Quantum World
 the rest of the course.
Weve thought about fast things. Now I want to think
about small things.
In physics were used thinking of things like energy as
continuous. But some things are digitized, like
charge. 1e, 2e, 11e OK; 1.4e is not
Ive described an nchannel enhancement mode MOSFET,
since I enhance the minority concentration near OX when I
apply +VG.
I can also build a pchannel depletion mode MOSFET.
G
S
p
D
  trapped
+ +
p
n bulk
+VDS
The layer near OX
is already inverted
with
Ive mentioned the Shroedinger equation; now I need to
explain it, using energy conservation.
For simplicity let me assume I have a perfect travelling
wave:
= ei(kx  t)
If I want to measure energy, what can I do? Differentiate.
d/dt = i ei(kx  t) = i
Tunneling for E < U0
E
L
Classically:
U
0
Always reflected!
E
QM
x
Exp
Decay
Some transmission!
[ Does this mean you can magically throw a bowling ball
through the wall? ]
[ Ive drawn the same wavelength on either side. Is that right? ]
T e2L
EX. L = 5 1
Review Compton
Heres another way to think of the Compton wavelength.
What is the wavelength of a photon whose energy is
equal to the rest energy of a particle of mass m?
E = hc/ = mc2
so
= h/mc !
We studied the electron Compton wavelength (a couple
pm),
Energy Quantization in Atoms
Ill start with a planetary model, since that is what I was
told in grade school. And Ill start with hydrogen, the
simplest atom.
v
e
Planck: Light is quantized, or
r
digitized, into chunks of nhf.
p+
18851962
Bohr 1913: perha
Introduce yourselves.
Modern Physics
HW #1,
Fri Sept. 6
TLearn
Quiz #1
Monday
on
Strange name: refers to physics 19001930!
Freshman or premed phys: Newton, Maxwell to
1900.
19001930: Newton/Maxwell usually OK, but only:
 slow stuff: v < c = 3 x 108 m/
Relativistic Energy
Momentum. Since the time between two events
depends on the reference frame, you might suspect
that true momentum is not what you saw in freshman
physics. Einstein found the correct momentum is
p = mu
refers to a particle, not a
frame:
Ultimate Composition: What is everything made
of?
Leptons such as the e are elementary.
There are six leptons, plus their antiparticles.
e


e
Neutrinos
These are not made of anything else.
m 200me , m 3500me. Otherwise quite similar.
Hadrons are made
Indeed, carbondiamond is an insulator, and Si is a
semiconductor, as you know.
C = [He]2s22p2. You know the pstate has an
occupancy of 6.
Si =
[Ne]3s23p2.
In both C and Si, there are four valence electrons, as
weve seen.
The C or Si lattice with covalen