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Young and Freedman - University Physics 11/e (Homework)

James Finch

Physics - College, section 1, Fall 2010

Instructor: Dr. Friendly

Current Score: 0/20

Due: Sunday, January 9, 2011 20:00 EST

Question
Points
1 2 3 4 5
0/2 0/3 0/3 0/5 0/7
Total
0/20

Description

Here are some textbook questions from University Physics 11/e by Young and Freedman published by Addison Wesley. Click here for a list of all of the questions coded in WebAssign.


Instructions

This demo assignment allows many submissions and allows you to try another version of the same question for practice.



1. –/2 points Notes Question: YF11 4.P.004.
Question part
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0/2
 
A man is dragging a trunk up the loading ramp of a mover's truck. The ramp has a slope angle of 20.0°, and the man pulls upward with a force F whose direction makes an angle of θ = 30.0° with the ramp (Fig. 4.26).

Figure 4.26
(a) How large a force F is necessary for the component Fx parallel to the ramp to be 75.0 N?
Enter a number.
N
(b) How large will the component Fy perpendicular to the ramp then be?
Enter a number.
N


2. –/3 points Notes Question: YF11 7.P.018.
Question part
Points
Submissions
1 2 3
0/1 0/1 0/1
0/50 0/50 0/50
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0/3
 
A slingshot will shoot a 14 g pebble 30.0 m straight up.
(a) How much potential energy is stored in the slingshot's rubber band?
Enter a number.
J
(b) With the same potential energy stored in the rubber band, how high can the slingshot shoot a 29 g pebble?
Enter a number.
m
(c) What physical effects did you ignore in solving this problem? (Select all that apply.)




3. –/3 points Notes Question: YF11 12.P.025.
Question part
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1 2 3
0/1 0/1 0/1
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0/3
 
Use the following result of Example 12.5 (Section 12.3) to calculate the following.

v_1 = sqrt((2GM)/R)

Here, v1 is the initial speed needed for a body to escape from the surface of a spherical mass M with radius R.
(a) Calculate the escape speed for a spacecraft from the surface of the Moon. Use the data in Appendix F.
Enter a number.
m/s
(b) Calculate the escape speed for an object from the surface of Saturn.
Enter a number.
m/s
(c) Why is the escape speed for a spacecraft independent of the spacecraft's mass?


4. –/5 points Notes Question: YF11 13.P.011.
Question part
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Submissions
1 2 3 4 5
0/1 0/1 0/1 0/1 0/1
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Jerk. A guitar string vibrates at a frequency of 470 Hz. A point at its center moves in SHM with an amplitude of 4.6 mm and a phase angle of zero.
(a) Write an equation for the position of the center of the string x in mm as a function of time t.
x(t) =
Enter a mathematical expression.
Click here to preview your answer.
(b) What are the maximum values of the magnitudes of the velocity and acceleration of the center of the string?
velocity
Enter a number.
m/s
acceleration
Enter a number.
m/s2
(c) The derivative of the acceleration with respect to time is a quantity called the jerk. Write an equation for the jerk of the center of the string j as a function of time, t (again, use the value of amplitude in mm).
j(t) =
Enter a mathematical expression.
Click here to preview your answer.
Find the maximum value of the jerk.
Enter a number.
mm/s3

Click here for help with symbolic formatting.

5. –/7 points Notes Question: YF11 22.P.006.
Question part
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0/1 0/1 0/1 0/1 0/1 0/1 0/1
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0/7
 
The three small spheres shown in Fig. 22.34 carry charges q1 = 3.35 nC, q2 = -7.50 nC, and q3 = 2.70 nC.

Figure 22.34
Find the net electric flux through each of the following closed surfaces shown in cross section in the figure.
(a) S1
Enter a number.
N·m2/C
(b) S2
Enter a number.
N·m2/C
(c) S3
Enter a number.
N·m2/C
(d) S4
Enter a number.
N·m2/C
(e) S5
Enter a number.
N·m2/C

(f) Do your answers to parts (a) through (e) depend on how the charge is distributed over each small sphere?
    


Why or why not?