Partners
Date
Name
HOMEWORK FOR LAB 2:
CHANGING MOTION
1. An object moving along
a line (the + position
axis) has the accelera-
tiontime graph on the
right.
Acceleration
a. Describe how the object might move to create this graph if it is moving
away

Chapter 0 Solutions
Circles
Learning Goal:
To calculate the circumference or area of a circle.
Every day, we see circles in compact disks, coins, and wheels, just to name a few examples.
Circles are also very common in math and physics, because they are e

PH211 Chapter5 Solutions
5.4.
I DENTIFY : For the maximum tension, the patient is just ready to slide so static friction is at its
maximum and the forces on him add to zero.
S ET U P : (a) The free-body diagram for the person is given in Figure 5.4a

64 WORKSHOP PHYSICS ACTIVITY GUIDE
d. How is the greater magnitude (size) of acceleration represented on an
acceleration vs. time graph?
Note: Please save your data for future use.
MATHEMATICAL DEFINITIONS OF
VELOCITY AND ACCELERATION
3.7. CALCULATI

51?. Two blocks are in contact on a frictionless table. A horizontal
force is applied to the larger block, as shown in Fig. 5-35. (a) If
m, = 2.3 kg, m2 = 1.2 kg, and F = 3.2 N, nd the magnitude of
the force between the two blocks. (b) Show that if a forc

Vectors Solutions
3.14. Visualize:
Solve: (a) We have A 5i 2 , B 3i 5 , and B 3i 5 . Thus, D A ( B) 8i 7 .
j
j
j
j
(b) Vectors A, B and D are shown in the above figure.
j
j
(c) Since D 8i 7 Dxi Dy , Dx 8 and Dy 7. Therefore, the magnitude and direction of

PH211 Projectile Motion Solutions
4.5. For a projectile, only vx and a y are constant during the flight. Since the acceleration ay g is down,
2
2
ax 0 and vx is constant. The nonzero a y is constantly changing v y , so the total speed v vx v y changes as

PH211 Motion-II Solutions
Questions:
2.7. (a) The slope of the position-versus-time graph is greatest at D, so the object is moving fastest at this point.
(b) The slope is negative at points C, D, and E, meaning the object is moving to the left at these p

Physics 211 Exam # 1
October 26,2006
234,105
, v
Name ké/ ggsrkie pd?
Instructions. Complete all the problems. Sketch the graphs as neatly as you can; i! it is linear, make
it look that way, if it is quadratic, then make it look quadratic. Include proper

Physics 211 Exam # 1
October 26,2006
Name
Instructions. Complete all the problems. Sketch the graphs as neatly as you can; if it is linear, make
it look that way, if it is quadratic, then make it look quadratic. Include proper units in all answers.
l. A

Chapter 6 Solutions Part 2
6.9. Visualize: Please refer to Figure EX6.9. Positive forces result in the object gaining speed and negative
forces result in the object slowing down. The final segment of zero force is a period of constant speed.
Solve: We hav

Physics 211 NAME_ ME/a KEV
EXAM #2
Fall 2007
Instructions: Complete all parts of the exam. Show all your work, include units whenever
necessary. Questions 1 8 are 5 points each, 9 13 are 12 points each.
PART I ~ Free Body Diagrams For each of the followin

2.6. (a) B. The object is still moving, but the magnitude of the slope of the position-versus-time curve is smaller
than at D.
(b) D. The slope is greatest at D.
(c) At points A, C, and E the slope of the curve is zero, so the object is not moving.
(d) At

PH211 Chapter 7 Solutions
7.4.
IDENTIFY: The energy from the food goes into the increased gravitational potential
energy of the hiker. We must convert food calories to joules.
SET UP: The change in gravitational potential energy is Ugrav mg ( yf yi ), whi

Chapter 3 Solutions
3.7.I DENTIFY and S ET U P :
Use Eqs. (3.4) and (3.12) to find
and
as functions of time. The
magnitude and direction of and can be found once we know their components.
E XECUTE : (a) Calculate x and y for t values in the range 0

PH211 Chapter 6 Solutions
6.5
.
IDENTIFY: The gravity force is constant and the displacement is along a straight line, so W Fs cos.
SET UP: The displacement is upward along the ladder and the gravity force is downward, so
1800 300 1500. w mg 735 N.
EXECU

Chapter 6 Solutions Part 1
6.17. (a) 2 t . Your constant push Fx provides the net force, so the puck accelerates with constant
acceleration ax
Fx
. From kinematics, with vix 0,
m
F
v ax t x t
m
If the mass is doubled, the time must also be doubled to re

Chapter 2 solutions
2.3.I DENTIFY : Target variable is the time
it takes to make the trip in heavy traffic. Use Eq. (2.2) that
relates the average velocity to the displacement and average time.
S ET U P :
so
and
E XECUTE : Use the information given

PH211 Chapter 4 Solutions
4.3.I DENTIFY : We know the resultant of two vectors of equal magnitude and want to find their magnitudes.
They make the same angle with the vertical.
Figure 4.3
S ET U P :
Take
to be upward, so
The strap on each side o

PH211 Chapter 10 Solutions
10.1. Model: We will use the particle model for the bullet (B) and the running student (S).
Visualize:
Solve: For the bullet,
KB =
1
1
m v 2 = (0.010 kg)(500 m/s)2 = 1250 J
2 B B 2
For the running student,
KS =
1
1
m v

Chapter 1 Solutions
1.8.I DENTIFY : Apply the given conversion factors.
S ET U P :
E XECUTE :
E VALUATE : A furlong is less than a mile and a fortnight is many hours, so the speed limit in mph is
a much smaller number.
1.11.
I DENTIFY :
We kn

Chapter 7 Solutions
7.17. Model: The two hanging blocks, which can be modeled as particles, together with the two knots where
rope 1 meets with rope 2 and rope 2 meets with rope 3 form a system. All the four objects in the system are in
static equilibrium