Review for Test #2
Responsible for:
- Chapters 5 & 6, sections 3-6, 7-1, 7-2, 12-1, 12-2, and
12-3* (also chapters 1-4)
- Notes from class
- Problems worked in class
- Homework assignments
Test format:
- 18 problems (5 points each)*
- multiple-choice, s
Chapter 13: Oscillatory Motion
We continue our studies of mechanics, but
combine the concepts of translational and rotational
motion.
We will revisit the ideal spring. In particular, we
will re-examine the restoring force of the spring and
its potential
The Simple Pendulum
An application of Simple Harmonic Motion
A mass m at the end of a massless
rod of length L
There is a restoring force
which acts to restore the
mass to =0
F = mg sin
Compare to the spring Fs=-kx
The pendulum does not
display SHM
Chapter 14: Wave Motion
We now leave our studies of mechanics and
take up the second major topic of the course
wave motion (though it is similar to SHM)
Wave a traveling disturbance which carries
energy from one point to another, but without the
transl
Sound Waves
Sound is a longitudinal wave
It requires a medium to convey it, e.g. a
gas, liquid, or solid
In a gas, the amplitude of the sound wave is
air pressure a series of slightly enhanced
(crest) and reduced (trough) pressure (or air
density) regi
Superposition, Interference, and
Standing Waves
In the first part of Chap. 14, we considered the
motion of a single wave in space and time
What if there are two waves present
simultaneously in the same place and time
Let the first wave have 1 and T1, w
Page 1
Test #4, PHYS 1111, Section
Nov. 25, 2002, Stancil
5 (12:20-1:10pm)
This is a multiple choice test of 13 questions. Give only one answer for
each question. Besure to enter your name and SSN on the form. You may keep
the question sheet.
1.
A sewing
Review for Test #1
Responsible for:
- Chapters 1, 2, 3, and 4 (except 3.6)
- Notes from class
- Problems worked in class
- Homework assignments
Test format:
- 18 problems (5 points each)*
- multiple-choice, some T/F, 2 bonus probs.
- Time: 75 minutes
T
Review for Test #3
Responsible for:
- Chapter 7 (7-3, 7-4), 8 (except 8-5), 9 (except 9-8), 10
(10-1 to 10-4); also chapters 1-7, 12
- Notes from class
- Problems worked in class
- Homework assignments
Test format:
- 18 problems (5 points each)*
- multi
Review for Test #4
Responsible for:
- Chapter 8 (8-5), 10 (10-5,10-6), 11, 13 (except 13-7,
13-8), 14 (14-1 to 14-4); also chapters 1-10, 12
- Notes from class
- Problems worked in class
- Homework assignments
Test format:
- 18 problems (5 points each)*
Orbital Motion of Satellites (12.3)
M
m
Satellites move in circular
(or more generally, elliptical)
orbits
Compute their period and
speed by applying Newtons
2nd Law in the radial direction
Orbital speed
Orbital
period
Example
Venus rotates slowly about
Chapter 12: Universal Force
due to Gravity
Every object in the Universe exerts an attractive force
on all other objects
The force is directed along the line separating two
objects
Because of the 3rd law, the force exerted by object 1
on 2, has the same
Static Equilibrium
In Chap. 6 we studied the equilibrium of pointobjects (mass m) with the application of Newtons
Laws
F
x
= 0,
F
y
=0
Therefore, no linear (translational) acceleration,
a=0
For rigid bodies (non-point-like objects), we can
apply anothe
Work done by a spring
We know that work equals force times
displacement
But how to we calculate the work due to a nonconstant force?
Reconsider the restoring force of a spring
Fs = kx
Hookes Law for the restoring
force of an ideal spring.
It depends o
Page 2
6.
In simple harmonic motion, the speed is greatest at that point in the
cycle when
a. the magnitude of the acceleration
is a maximum
b. the displacement
is a maximum
,(JO q~o
@ the magnitude of the acceleration is a minimum
d. the potential energy
Chapter 7: Energy and Work
Alternative method for the study of motion
In many ways easier, gives additional
information
Kinetic energy: consider an object of mass m
and speed v, we define the kinetic energy as
2
1
K
2
- a scalar, not a vector
- units k
Page 1
Test #1, PHYS 1111, Section
5 (12:20-1:
;
Opm) , Stancil
This is a multiple choice test of 15 questions. Give only one answer
each question. Besure to enter your name and SSN on the form.
1.
for
A boy throws a ball with an initial velocity of 25 m/
Potential Energy and Conservation of
Energy
Work Done by Gravity
If one lifts an object of mass m from the floor
(yi=0) to a height yf=h, you have done work on the
object
W = F cos y = mg( y f y i ) = mgh
We have imparted energy to it, but it is at rest
Page 2
6.
The horizontal and vertical components of the initial velocity of a
football are 24 m/s and 7 m/s respectively. What is the initial velocity
of the football?
,J
a. 31 m/s
Voy "'",2.A1'l j
I
",
(V
@25m/s
c. 17m/ s
d. 42 m/s
7.
J
Vo .:
~I(').
7I
=
Example problem
If it takes 4.00 J of work to stretch a
Hookes law spring 10.0 cm from its
unstretched length, determine the extra
work required to stretch it an additional
10.0 cm.
Conservative and Non-conservative Forces
Conservative Force: a force fo
Page 3
11. A bullet is fired with a certain velocity at an angle 8 above the
horizontal at a location where g = 10.0 m/s2. The initial x and y
components of its velocity are 86.6 m/s and 50 m/s respectively. What is
the initial velocity of the bullet?
a.
Chapter 9: Impulse,
Momentum, and Collisions
Up to now we have considered forces which have a
constant value (does not depend on time) throughout
the motion and no explicit time duration
Now, lets consider a force which has a time duration
(usually shor
Example
A 45-kg swimmer runs with a horizontal velocity of
+5.1 m/s off of a boat dock into a stationary 12-kg
rubber raft. Find the velocity that the swimmer and
raft would have after impact, if there were no
friction and resistance due to the water.
Sol
Chapter 10. Rotational Kinematics
Up to now, we have only considered pointparticles, i.e. we have not considered their shape
or size, only their mass
Also, we have only considered the motion of
point-particles straight-line, free-fall, projectile
motion
Chapter 11. Rotational Dynamics
As we did for linear (or translational) motion,
we studied kinematics (motion without regard to
the cause) and then dynamics (motion with regard
to the cause), we now proceed in a similar fashion
We know that forces are r