Essential University Physics
4th Edition
ISBN: 9780134988559
Author: Wolfson, Richard
Publisher: Pearson Education,
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Textbook Question
Chapter 7, Problem 9E
Determine the work you would have to do to move a block of mass m from point 1 to point 2 at constant speed over the two paths shown in Fig. 7.15. The coefficient of friction has the constant value μ over the surface. Note: The diagram lies in a horizontal plane.
FIGURE 7.15 Exercises 10 and 11
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Check out a sample textbook solutionStudents have asked these similar questions
(a) A block with a mass m is pulled along a horizontal surface for a distance x by a constant force at an angle ? with respect to the horizontal. The coefficient of kinetic friction between block and table is μk. Is the force exerted by friction equal to μkmg? If not, what is the force exerted by friction? (Assume ? is measured above the horizontal.)
This answer has not been graded yet.
(b) How much work is done by the friction force and by ? (Don't forget the signs. Use the following as necessary: F for the magnitude of , g, m, x, ? and μk.)
Wfk
=
WF
=
(c) Identify all the forces that do no work on the block. (Select all that apply.)
cos(?)m sin(?)friction k
(d) Let m = 2.00 kg, x = 4.40 m, ? = 3.2°, F = 15.5 N, and μk = 0.400, and find the answers to parts (a) and (b). (Include appropriate signs.)
fk
=
N
WF
=
J
Wfk
=
The potential energy function associated with a force acting on a system is U =
(Express your answer in vector form.)
F =
3x7y y 2x. What is the force at point (x, y)?
(a) A block with a mass m is pulled along a horizontal surface for a distance x by a constant force F at an angle e with respect to the horizontal. The coefficient of kinetic friction
between block and table is u. Is the force exerted by friction equal to u, mg? If not, what is the force exerted by friction? (Assume 0 is measured above the horizontal.)
This answer has not been graded yet.
(b) How much work is done by the friction force and by F? (Don't forget the signs. Use the following as necessary: F for the magnitude of F, g, m, x, 0 and u,)
WE =
(c) Identify all the forces that do no work on the block. (Select all that apply.)
O friction f
OF Cos(e)
OF sin(0)
O mE
(d) Let m = 2.00 kg, x = 4.50 m, 0 = 3.7°, F = 14.5 N, and u, = 0.400, and find the answers to parts (a) and (b). (Include appropriate signs.)
We =
W =
Chapter 7 Solutions
Essential University Physics
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