(a)
The work done by the
(a)
Answer to Problem 1SP
The work done by the
Explanation of Solution
Given Info: The distance moved by the block is
Write the equation for the work done.
Here,
Substitute
Conclusion:
Thus the work done by the
(b)
The work done by the net force acting upon the block.
(b)
Answer to Problem 1SP
The work done by the net force acting upon the block is
Explanation of Solution
Given Info: There are two horizontal forces acting on the block;
Write the equation for the net force acting on the block.
The difference is taken since the force are acting opposite to each other.
Substitute
Conclusion:
Thus the work done by the net force acting upon the block is
(c)
The value which among the two work done should be used to find the increase in kinetic energy of the block.
(c)
Answer to Problem 1SP
The work done by the net force acting upon the block found in part (b) should be used to find the increase in kinetic energy of the block.
Explanation of Solution
Kinetic energy of an object is the energy of the object associated with its motion. The kinetic energy is equal to one-half the mass of the object times the square of its speed. Work is the force times displacement of an object.
Doing work on an object increases its energy. Since the work involves the transfer of energy, the amount of kinetic energy gained by the object should be equal to the amount of net work done on it. If the object was initially at rest, the work done on the object become equal to its kinetic energy.
The work done by the net force is the net work done on the block. The increase in kinetic energy is equal to the net work done on the object.
Conclusion:
Thus the work done by the net force acting upon the block found in part (b) should be used to find the increase in kinetic energy of the block.
(d)
What happens to the energy added to the system via the work done by the
(d)
Answer to Problem 1SP
The
Explanation of Solution
The principle of conservation of energy states that energy can neither be created nor be destroyed. It can only be converted from one form to another so that total energy remains constant.
The increase in kinetic energy of the block is
The frictional force is opposing the motion of the block. Remaining energy is used to oppose this frictional force and it is thus converted into thermal energy. All of the energy produced by the
Conclusion:
Thus the
(e)
The kinetic energy and velocity of the block at the end of
(e)
Answer to Problem 1SP
The kinetic energy of the block is
Explanation of Solution
Given Info: The mass of the block is
If the object was initially at rest, the net work done on the object become equal to its kinetic energy.
Here,
Write the equation for kinetic energy.
Here,
Rewrite the above equation for
Substitute
Conclusion:
Thus the kinetic energy of the block is
Want to see more full solutions like this?
Chapter 6 Solutions
PHYSICS OF EVERYDAY PHENO... 7/14 >C<
- College PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningUniversity Physics (14th Edition)PhysicsISBN:9780133969290Author:Hugh D. Young, Roger A. FreedmanPublisher:PEARSONIntroduction To Quantum MechanicsPhysicsISBN:9781107189638Author:Griffiths, David J., Schroeter, Darrell F.Publisher:Cambridge University Press
- Physics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningLecture- Tutorials for Introductory AstronomyPhysicsISBN:9780321820464Author:Edward E. Prather, Tim P. Slater, Jeff P. Adams, Gina BrissendenPublisher:Addison-WesleyCollege Physics: A Strategic Approach (4th Editio...PhysicsISBN:9780134609034Author:Randall D. Knight (Professor Emeritus), Brian Jones, Stuart FieldPublisher:PEARSON