Physics 141
Problem Set 4, Newtons Laws
Problem 1. A passenger sitting in the rear of a bus claims that he was injured when the driver slammed on the
brakes, causing a suitcase to come ying toward him from the front of the bus. If you were the judge in th
Physics 141
Problem Set 2, Motion in One Dimension
Due September 12, 2014
Problem 1. If the average velocity of an object is zero in some time interval, what can you say about its displacement
in that interval? What about its distance travelled? Explain y
Physics 141
Problem Set 7, Mechanical Energy
Due October 20, 2014
Problem 1. A person drops a ball from the roof of a building while a second person observes the motion of the
ball from the ground. Both people are stationary. Will the people agree on the
Physics 141
Problem Set 2, Motion in One Dimension
Problem 1. If the average velocity of an object is zero in some time interval, what can you say about its displacement
in that interval? What about its distanced travelled? Explain your answers.
You know
Physics 141
Problem Set 1, Units and Vectors
Problem 1. A creature moves at a speed of 5 furlongs per fortnight. Convert the speed to m/s given that a furlong
is 220 yards and a fortnight is 2 weeks. The creature is probably a snail or some other very slo
Exam 1
PHYSICS 140/141
Firstname
October 2, 2014
Lastname
Circle your lab section
140 LeRoy
141-002A M 8-11 Jorge Palos-Chavez
141-002B M 12-3 Huanian Zhang
141-002C M 3-6 Ashoordin Ashoormaram
141-002D M 6-9 Ashoordin Ashoormaram
141-001E T 9-12 Erika Wa
Physics 141 Equations
v = dr
a = dv
v = v0 + at
dt
dt
1 2
r = r0 + v0 t + 2 at |g| = 9.8m/s2
Fext = ma
w = mg
|fs | s |n|
d|vtang |
2
|fk | = k |n| |acent | = vtang /r |atang | = dt
x
W = xif F dx
Ktrans = 1 mv 2 Wnet = K
2
dW
1
P = dt = F v
Ugrav = mgy U
Physics 141
LAB
Fall 2014
A student is graded on the basis of 12 labs (11 for Monday students) and
associated reports, lab quizzes, worksheets, and a lab practical at the end of the semester.
Each individual student is required to write their own unique a
PHYSICS 140/141 - Fall 2014
INSTRUCTOR:
PHONE:
WEBPAGE:
LECTURE:
Brian LeRoy
OFFICE: PAS 547
626-4726
EMAIL: leroy@physics.arizona.edu
http:/d2l.arizona.edu
MWF 10:00-10:50 in PAS 201
REQUIRED TEXTBOOKS:
University Physics by Young & Freedman (13th editio
Physics 141
Problem Set 1, Units and Vectors
Due August 29, 2014
Problem 1. A creature moves at a speed of 5 furlongs per fortnight. Convert the speed to m/s given that a furlong
is 220 yards and a fortnight is 2 weeks. The creature is probably a snail or
Physics 141
Problem Set 3, Motion in Two Dimensions
Due September 19, 2014
Problem 1. If you know the position vectors of a particle at two points along its path and also know the time
interval during which it moved from one point to the other, can you de
Physics 141
Problem Set 3, Motion in Two Dimensions
Problem 1. If you know the position vectors of a particle at two points along its path and also know the time
interval during which it moved from one point to the other, can you determine the particles i
Physics 141
Problem Set 6, Work
Due October 13, 2014
Problem 1. As a simple pendulum swings back and forth, the forces acting on it are gravity, the tension in the
supporting cord and air resistance. (a) Which of these forces, if any, does no work on the
Physics 141
Problem Set 5, Circular Motion
Due October 6, 2014
Problem 1. A rubber stopper on the end of a string is swung steadily in a horizontal circle. In one trial, it moves
at speed v in a circle of radius r. In a second trial, it moves at a higher
Physics 141
Problem Set 8, Linear Momentum
Due October 27, 2014
Problem 1. While in motion, a pitched baseball has kinetic energy and linear momentum. (a) Can we say that
it has a force that it can exert on any object it strikes? (b) Can the baseball deli
Physics 141
Problem Set 4, Newtons Laws
Due September 29, 2014
Problem 1. A passenger sitting in the rear of a bus claims that he was injured when the driver slammed on the
brakes, causing a suitcase to come ying toward him from the front of the bus. If y
Physics 141 Answers
Problem Set 1, Units and Vectors
Problem 1. 8.3 104 m/s
Problem 2. 1.5 104 m.
Problem 3. Two vectors, not possible. Three vectors, possible.
Problem 4. 1 km south, 0.
Problem 5. 537.26 ft horizontal and 48.22 ft vertical, 539.41 ft at