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

WebAssign

Welcome, demo@demo

(sign out)

Tuesday, April 1, 2025 06:08 EDT

Home My Assignments Grades Communication Calendar My eBooks

Katz - Physics for Scientists and Engineers 1/e (Homework)

James Finch

Physics - College, section 1, Fall 2019

Instructor: Dr. Friendly

Current Score : 14 / 42

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

Last Saved : n/a Saving...  ()

Print Assignment
Question
Points
1 2 3 4 5 6 7 8 9 10 11
5/11 4/10 0/5 2/2 0/1 1/1 –/2 2/3 –/3 –/2 0/2
Total
14/42 (33.3%)

  • Instructions

    Physics for Scientists and Engineers: Foundations and Connections 1st edition, by Debora M. Katz, improves student outcomes through greater engagement, enhanced interactivity, and superior content. The WebAssign complement of this course includes end-of-chapter questions from the textbook, a wide variety of tutorials with interactive simulations and videos, and exclusive additional questions with solutions and feedback.

    Question 1 features an Integrated Tutorial which takes the student through the process of figuring out the problem, asking questions they will learn to ask themselves when faced with new problems.

    Question 2 showcases a Pre-Lecture Exploration simulation so that students can make predictions, change parameters, and observe results.

    Question 3 is an Interactive Video Vignette (IVV) question. IVVs encourage students to address their alternate conceptions outside of the classroom. They include online video analysis and interactive individual tutorials to address learning difficulties identified by PER (Physics Education Research).

    Question 4 has a Master It tutorial that lets students assess and re-tune their understanding of the material.

    Question 5 has a Watch It video created by Debora Katz, the author of the textbook.

    Question 6 is a Reading Comprehension multiple choice question that is designed to help students prepare for class by reading the textbook, and to gauge their understanding of assigned readings.

    Questions 7 and 8 have fully worked-out solutions for the problems.

    The WebAssign complement of this course includes over 1,800 questions from WebAssign's original University Physics collection, which feature answer feedback for every question part, detailed and stepped-out solutions for every question, and a selection of multi-part tutorials.

    Questions 10 and 11 are from this collection, with question 10 featuring a multi-step tutorial.

    View the complete list of WebAssign questions available for this textbook. 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.

    The answer key and solutions will display after the first submission for demonstration purposes. Instructors can configure these to display after the due date or after a specified number of submissions.

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. 5/11 points  |  Previous Answers KatzPSEf1 5.IT.002. My Notes
Question Part
Points
Submissions Used
1 2 3 4 5 6 7 8 9 10 11
1/1 1/1 1/1 0/1 1/1 1/1 –/1 –/1 –/1 –/1 –/1
3/50 1/50 1/50 3/50 2/50 1/50 0/50 0/50 0/50 0/50 0/50
Total
5/11
 
Integrated Tutorial
On April 23, 2002, a passenger train about 35 miles outside of Los Angeles was hit by a freight train. The accident killed two and injured more than 260 people on the passenger train. News reports said that the passenger train came to a complete stop before the collision, and afterward the two trains were locked together moving in the freight train's original direction.

Some people believe the force on the passenger train could have been reduced and perhaps eliminated if it had sped up so that its speed matched that of the freight train instead of stopping before the collision. In this problem we explore that possibility by considering a head-on collision between two particles in two different cases:
Case 1: if particle B was at rest before the collision, and
Case 2: if particle B was moving toward particle A with a speed equal to that of particle A.
In both cases, before the collision particle A is moving at 29.1 m/s toward particle B, the duration of the collision is 1.90 ms, and after the collision particle B is moving at 11.1 m/s in particle A's original direction. Particle B has a mass of 6.76 kg. To keep this problem simple, assume the only force exerted on particle B is due to particle A, and assume the acceleration is constant. Find the magnitude of the force exerted by particle A on particle B. (The mass for particle A can be different in each case.)
Part 1 of 11 - Interpret and Anticipate
This problem involves a special case of one-dimensional kinematics with constant acceleration. We are asked to find the magnitude of the force exerted on particle B in both cases. To do so, we will first need to find the particle's acceleration. The two final answers should be numerical and have the SI units of force. What are the units of force? (Select all that apply.)
Correct: Your answer is correct.

Our goal is to see if the force in Case 2 in which particle B is moving toward particle A is lower (perhaps even zero) compared to Case 1 in which particle B is at rest before the collision.
Part 2 of 11 - Interpret and Anticipate (cont.)
Once we know particle B's acceleration, what principle will we need to apply to find the force?
     Correct: Your answer is correct.
Correct. Since only the force exerted by particle A acts on particle B, we use the acceleration and mass to find this force.
Part 3 of 11 - Interpret and Anticipate (cont.)
In Case 1, particle B is at rest before the collision. We must first find particle B's acceleration. Which sketch best applies to this task?

Correct: Your answer is correct.
Correct. This sketch shows the relevant information: particle B is at rest before the collision and particle B is moving in the same direction as particle A's original direction after the collision. Also, a coordinate system is needed when we solve kinematics problems.
Part 4 of 11 - Solve
When solving a problem involving constant acceleration, it is best to list the five variables. We create our list using the coordinate system from our sketch. To find the best constant acceleration equation, we only need to know if each variable is known, needed, or not needed; we don't need to know the values of each variable at this time.

Which variables are known? (Select all that apply.)
Incorrect: Your answer is incorrect.

Part 5 of 11 - Solve (cont.)
Which variable will we need to find the value of to solve this problem?
     Correct: Your answer is correct.
Correct.
Part 6 of 11 - Solve (cont.)
Using the variables we know and need, which equation is best to use for this problem?
     Correct: Your answer is correct.
Correct.
Part 7 of 11 - Solve (cont.)
Now, we are ready to calculate particle B's acceleration from
vx = v0x + axt.
 Solve for ax and substitute values. Remember particle B's initial velocity is zero for Case 1.

The acceleration in Case 1 is given by:
ax = m/s2.


Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
2. 4/10 points  |  Previous Answers KatzPSEf1 5.PLE.002. My Notes
Question Part
Points
Submissions Used
1 2 3 4 5 6 7 8 9 10
1/1 1/1 1/1 1/1 0/1 –/1 –/1 –/1 –/1 –/1
2/50 2/50 3/50 1/50 1/50 0/50 0/50 0/50 0/50 0/50
Total
4/10
 
This question has several parts that must be completed sequentially. If you skip a part of the question, you will not receive any points for the skipped part, and you will not be able to come back to the skipped part.

Prelecture Exploration: Atwood Machine
When two massive objects are suspended on opposite sides of a pulley, the arrangement is called an Atwood machine. Two friends, Makena and Dani, are studying physics together, and they decide to delve further into understanding this arrangement.

In this simulation, the cord that connects the two masses is ideal; that is, it is inextensible (does not stretch) and its mass is negligible. Also, the pulley is frictionless with negligible mass, and any air resistance can be neglected. The forces and accelerations of the two masses are shown, along with the tension in the cord.

The sign convention for motion is defined as shown by the arrows. Makena and Dani can change the mass of m1 and m2 by using the sliders. They then can click "start" to set the system in motion.


Click here to open the simulation in a new window.
Part 1 of 9 - Accelerations in an Atwood Machine
Dani and Makena examine the figure shown.
The friends consider the situation for which the mass m1 is initially moving downward. Makena and Dani discuss the acceleration in this case. Which of Makena's statements could be correct?
     Correct: Your answer is correct.
Makena is correct. She realizes that the rope connects the masses, so if one accelerates, both will accelerate, but she has no knowledge of the masses involved, so nothing definite can be said about the motion of the system without knowing the masses.
Part 2 of 9 - Acceleration of the System
Makena and Dani finally realize that because the masses are connected by an inextensible cord, if one goes down, the other must be going up.

The two friends decide to use a simulation to gain a better understanding of an Atwood machine. Dani sets the masses equal to any particular values, with
m2 > m1.
 What can Makena say about the magnitudes of the acceleration of m1 and m2?
     Correct: Your answer is correct.
Makena is correct. The accelerations are equal for any values of m1 and m2. What is the reason they are the same?
Part 3 of 9 - Tension in the Cord
The friends realize that the acceleration magnitudes are equal for any nonzero values of m1 and m2. For
m2 > m1,
 Makena and Dani take T1 and T2 to be the magnitudes of the tension in the cord connected to m1 and m2, respectively. Which of Makena's statements is true?
     Correct: Your answer is correct.
Makena is correct. For a frictionless pulley and cord of negligible mass, the tension is the same throughout the cord, so the magnitudes of the tension forces acting on the two masses are the same.
Part 4 of 9 - Tension in the Cord
Dani and Makena consider the case for which m2 > m1. If the tension is constant throughout the cord, how can Dani explain why it is that the two masses accelerate?
     Correct: Your answer is correct.
Dani is correct. For example, for m1, the net force is the vector sum of the weight of m1 and the tension in the cord connected to it, which, for
m1 ≠ m2
 and
m1 ≠ 0,
 is nonzero, so there is a resulting acceleration.
Part 5 of 9 - Limiting Behavior
The women consider the limiting case where
m2 → ∞,
 whereas m1 remains some constant (fixed) value. What value does Dani say the magnitude of the acceleration approaches?
    


Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
3. 0/5 points  |  Previous Answers KatzPSEf1 10.IVV.001. My Notes
Question Part
Points
Submissions Used
1 2 3 4 5
–/1 –/1 0/1 –/1 0/1
0/50 0/50 1/50 0/50 1/50
Total
0/5
 
Watch the video vignette below, and be sure to follow any instructions when prompted during the videos. Then answer the questions below about the concepts discussed in the video.
(a)
As you saw in the video, the two bullets in the experiment were fired from the same rifle. Assume the bullets also had the same mass and were fired from identically prepared cartridges. From this, what can we conclude about the initial momentum of the bullets just before they struck the blocks?
    
(b)
As you saw in the video, the two blocks had about the same mass, and both were initially at rest. Which of the following is true about the two bullet–block systems, just after the bullets collided with their respective blocks?
    
(c)
Which of the following statements provides correct reasoning for why both bullet–block systems reached the same maximum height?
     Incorrect: Your answer is incorrect.
(d)
Which of the following statements are true about the energy of the two bullet–block systems immediately after the collisions? (Select all that apply.)

(e)
Imagine comparing the two blocks after the experiment. In which block would we expect the bullet to be embedded the greatest distance?
     Incorrect: Your answer is incorrect.
Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
4. 2/2 points  |  Previous Answers KatzPSEf1 5.P.027.MI. My Notes
Question Part
Points
Submissions Used
1 2
1/1 1/1
2/50 3/50
Total
2/2
 
A particle of mass m1 accelerates at 4.45 m/s2 when a force F is applied. A second particle of mass m2 experiences an acceleration of only 1.50 m/s2 under the influence of this same force F.
(a) What is the ratio of m1 to m2?
m1
m2
 = Correct: Your answer is correct.


(b) If the two particles are combined into one particle with mass
m1 + m2,
 what is the acceleration of this particle under the influence of this force F?
Correct: Your answer is correct. m/s2

Need Help? Master It

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
5. 0/1 points  |  Previous Answers KatzPSEf1 5.P.042. My Notes
Question Part
Points
Submissions Used
1
0/1
1/50
Total
0/1
 
Find an expression for the cart's acceleration in the figure below in terms of the ball's mass m and the angle θ. (Use any variable or symbol stated above along with the following as necessary: g. Assume θ is measured with respect to the vertical.)
a =
√
Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
6. 1/1 points  |  Previous Answers KatzPSEf1 5.RC.006. My Notes
Question Part
Points
Submissions Used
1
1/1
2/50
Total
1/1
 
Which of these forces encountered in everyday settings is considered a fundamental force?
     Correct: Your answer is correct.
Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
7. –/2 points KatzPSEf1 5.P.025. My Notes
Question Part
Points
Submissions Used
1 2
–/1 –/1
0/50 0/50
Total
–/2
 
The starship Enterprise has its tractor beam locked onto some valuable debris and is trying to pull it toward the ship. A Klingon battle cruiser and a Romulan warbird are also trying to recover the item by pulling the debris with their tractor beams as shown in the figure below.
(a) Given the following magnitudes of the tractor beam forces, find the net force experienced by the debris:
FEnt = 8.40 ✕ 106 N,
FRom = 2.15 ✕ 106 N,
 and
FKling = 8.05 ✕ 105 N.
 (Express your answer in vector form. Assume the debris is at the origin, the Klingons are along the +x axis and the Enterprise is along the +y axis.)
Fnet =
√
N

(b) If the debris has a mass of 2549 kg, what is the net acceleration of the debris? (Express your answer in vector form.)
anet =
m/s2
Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
8. 2/3 points  |  Previous Answers KatzPSEf1 5.P.029. My Notes
Question Part
Points
Submissions Used
1 2 3
0/1 1/1 1/1
4/50 1/50 4/50
Total
2/3
 
Two forces
F1 = (68.50i − 26.83j) N
 and
F2 = (27.41i − 80.52j) N
 are exerted on a particle. The particle's mass is 19.57 kg.
(a) Find the particle's acceleration in component form. (Express your answer in vector form.)
a =
(95.91ˆi−299.14ˆj)
Incorrect: Your answer is incorrect. m/s2

(b) What are the magnitude and direction of the acceleration?
magnitude     Correct: Your answer is correct. m/s2
direction     Correct: Your answer is correct. ° counterclockwise from the +x axis
Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
9. –/3 points KatzPSEf1 5.P.046. My Notes
Question Part
Points
Submissions Used
1 2 3
–/1 –/1 –/1
0/50 0/50 0/50
Total
–/3
 
A heavy crate of mass 48.0 kg is pulled at constant speed by a dockworker who pulls with a 330-N force at an angle θ with the horizontal (see figure below). The magnitude of the friction force between the crate and the pavement is 209 N.
(a) Draw a free-body diagram of the forces acting on the crate.


(b) What is the angle θ of the rope with the horizontal?
°

(c) What is the magnitude of the normal force exerted by the pavement on the crate?
N
Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
10. –/2 points KatzPSEf1 5.WA.08.008.Tutorial. My Notes
Question Part
Points
Submissions Used
1 2
–/1 –/1
0/50 0/50
Total
–/2
 
A contestant in a winter games event pushes a 55.0-kg block of ice across a frozen lake with a force of 25 N at 32.0° below the horizontal as shown in Figure (a) below, and it moves with an acceleration of 0.390 m/s2 to the right.
(a) What is the normal force exerted by the lake surface on the block of ice?
N

(b) Instead of pushing on the block of ice, the contestant now pulls on it with a rope at the same angle above the horizontal as in part (a), and with the same magnitude of force. See Figure (b) above. Now what is the normal force exerted by the lake surface on the block of ice?
N

Need Help? Master It

Your work in question(s) will also be submitted or saved.
Viewing Saved Work Revert to Last Response
11. 0/2 points  |  Previous Answers KatzPSEf1 5.WA.06.013. My Notes
Question Part
Points
Submissions Used
1 2
0/1 0/1
1/50 1/50
Total
0/2
 
Tom enlists the help of his friend John to move his car. They apply forces to the car as shown in the diagram. Here
|F1| = 426 N,
|F2| = 385 N
 and friction is negligible. Mass of the car = 3.50 103 kg, θ1 = 12.0°, and θ2 = 25.0°. The diagram below shows the top view of the car which is in the x-z plane (horizontal plane).

(a) Find the resultant force exerted on the car. (Express your answer in vector notation.)
Fnet
 =
769.2
Incorrect: Your answer is incorrect.
Did you consider the components of the forces in the x and z directions? Review rules for vector addition. N

(b) What is the acceleration of the car? (Express your answer in vector notation.)
a
 =
0.21977
Incorrect: Your answer is incorrect.
How is the net force on an object related to its acceleration? m/s2
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 a number.
Enter a number.
Enter a number.
Enter a number.
Enter a number.
Enter a number.
Enter a number.
Enter a number.