WebAssign is not supported for this browser version. Some features or content might not work. System requirements

WebAssign

Welcome, demo@demo

(sign out)

Thursday, April 3, 2025 14:04 EDT

Home My Assignments Grades Communication Calendar My eBooks

Cutnell and Johnson - Physics 9/e (Homework)

James Finch

Physics - College, section 1, Fall 2019

Instructor: Dr. Friendly

Current Score : 3 / 16

Due : Monday, January 28, 2030 00:00 EST

Last Saved : n/a Saving...  ()

Print Assignment
Question
Points
1 2 3 4 5 6 7
–/3 2/2 1/1 –/4 –/1 –/2 –/3
Total
3/16 (18.8%)

  • Instructions

    Physics 9/e by Cutnell and Johnson published by John Wiley & Sons, Inc. is now a WebAssignPLUS selection. WebAssignPLUS includes a complete on-line version of the text, the Student Study Guide, the Student Solutions Manual, and a variety of interactive study aids. All of these rich resources are linked together in a dynamic and interactive environment for students. Additional links to the eBook within each problem are structured to support the way students work and provide them with superior just-in-time learning resources. Also the eBook availability provides students with a significantly less expensive option than the printed version.

    Questions 1 and 7 are symbolic problems, which ask students to solve a problem using only symbolic manipulation. These questions employ WebAssign's physPad answer entry palette to allow students to easily and naturally enter physics notation required for their answer.

    Questions 2, 3, and 5 are standard end of chapter questions.

    Question 4 is a end of chapter problem that is enhanced with an optional Guided Online (GO) tutorial. Each GO tutorial steps a student through a similar question with feedback enhanced multiple choice questions similar to the Focus on Concept questions. Other questions within the tutorial help students solve the problem symbolically to aid in mastering the underlying concepts involved in the problem

    Question 6 is a simulation problem with a link to a simulation that will help the student visualize the concept.

    Click here for a list of all of the questions coded in WebAssign. This demo assignment allows many submissions and allows you to try another version of the same question for practice wherever the problem has randomized values.

Assignment Submission

For this assignment, you submit answers by question parts. The number of submissions remaining for each question part only changes if you submit or change the answer.

Assignment Scoring

Your last submission is used for your score.

1. –/3 points CJ9 4.P.092. My Notes
Question Part
Points
Submissions Used
1 2 3
–/1 –/1 –/1
0/50 0/50 0/50
Total
–/3
 
A small sphere is hung by a string from the ceiling of a van. When the van is stationary, the sphere hangs vertically. However, when the van accelerates, the sphere swings backward so that the string makes an angle of θ with respect to the vertical.
(a) Derive an expression for the magnitude a of the acceleration of the van in terms of the angle θ and the magnitude g of the acceleration due to gravity.


(b) Find the acceleration of the van when θ = 29.7°.
m/s2

(c) What is the angle when the van moves with a constant velocity?
°

Additional Materials

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
2. 2/2 points  |  Previous Answers CJ9 17.P.061. My Notes
Question Part
Points
Submissions Used
1 2
1/1 1/1
2/50 4/50
Total
2/2
 
The two speakers in the drawing are vibrating in phase, and a listener is standing at point P. Does constructive or destructive interference occur at P when the speakers produce sound waves whose frequency is the following? Justify your answers with appropriate calculations. Take the speed of sound to be 343 m/s. (Do this on paper. Your instructor may ask you to turn in this work.)
(a) 1466 Hz
     Correct: Your answer is correct.

(b) 977 Hz
     Correct: Your answer is correct.

Additional Materials

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
3. 1/1 points  |  Previous Answers CJ9 4.P.099. My Notes
Question Part
Points
Submissions Used
1
1/1
2/50
Total
1/1
 
A student presses a book between his hands, as the drawing indicates. The forces that he exerts on the front and back covers of the book are perpendicular to the book and are horizontal. The book weighs 29 N. The coefficient of static friction between his hands and the book is 0.32. To keep the book from falling, what is the magnitude of the minimum pressing force that each hand must exert?
Correct: Your answer is correct. N

Additional Materials

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
4. –/4 points CJ9 4.P.044.GO. My Notes
Question Part
Points
Submissions Used
1 2 3 4
–/1 –/1 –/1 –/1
0/50 0/50 0/50 0/50
Total
–/4
 
A person pushes on a 55-kg refrigerator with a horizontal force of -277 N; the minus sign indicates that the force points in the −x direction. The coefficient of static friction is 0.74.
(a) If the refrigerator does not move, what are the magnitude and direction of the static frictional force that the floor exerts on the refrigerator?
Static frictional force =

(b) What is the magnitude of the largest pushing force that can be applied to the refrigerator before it just begins to move? Assume g = 9.81 m/s2.
Magnitude of largest force =
GO Tutorial

Additional Materials

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
5. –/1 points CJ9 4.P.066. My Notes
Question Part
Points
Submissions Used
1
–/1
0/50
Total
–/1
 
The person in the drawing is standing on crutches. Assume that the force exerted on each crutch by the ground is directed along the crutch, as the force vectors in the drawing indicate. If the coefficient of static friction between a crutch and the ground is 1.26, determine the largest angle θMAX that the crutch can have just before it begins to slip on the floor.
°

Additional Materials

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
6. –/2 points CJ9 1.P.051. My Notes
Question Part
Points
Submissions Used
1 2
–/1 –/1
0/50 0/50
Total
–/2
 
As an aid in working this problem, consult Concept Simulation 1.1.

On a safari, a team of naturalists sets out toward a research station located 7.2 km away in a direction 42° north of east. After traveling in a straight line for 3.5 km, they stop and discover that they have been traveling 21° north of east, because their guide misread his compass. What are the magnitude and direction (relative to due east) of the displacement vector now required to bring the team to the research station?
magnitude km
direction ° (north of due east)

Additional Materials

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
7. –/3 points CJ9 9.P.007. My Notes
Question Part
Points
Submissions Used
1 2 3
–/1 –/1 –/1
0/50 0/50 0/50
Total
–/3
 
A pair of forces with equal magnitudes, opposite directions, and different lines of action is called a "couple." When a couple acts on a rigid object, the couple produces a torque that does not depend on the location of the axis. The drawing shows a couple acting on a tire wrench, each force being perpendicular to the wrench. Determine an expression for the torque produced by the couple when the axis is perpendicular to the tire and passes through the following. Express your answers in terms of the magnitude F of the force and the length L of the wrench.
(a) point A
τ =


(b) point B
τ =


(c) point C
τ =

Additional Materials

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
Home My Assignments
Enter a number.
Enter an exact number.
Enter a number.
Enter a number.
Enter a number.
Enter a number.
Enter a number.
Enter a number.