Concept explainers
A force
(a)
The work done on the particle by the force.
Answer to Problem 7.11P
The work done on the particle is
Explanation of Solution
Given info: A force vector
From the properties of dot products, the relation of unit like vectors is,
From the properties of dot products, the relation of unit unlike vectors is,
The expression for the work done on the particle is,
Here,
Substitute
Substitute
Conclusion:
Therefore, the work done on the particle is
(b)
The angle between
Answer to Problem 7.11P
The angle between
Explanation of Solution
From part (a), the work done on the particle by the force is,
The equation of work done on the particle is,
Here,
The force vector is expressed as,
Here,
Compare the given force vector with the above equation, the value of
The magnitude of force vector is,
Substitute
The displacement vector is expressed as,
Here,
Compare the given displacement vector with the above equation, the value of
The magnitude of displacement vector is,
Substitute
Substitute
Conclusion:
Therefore, the angle between
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Chapter 7 Solutions
EBK PHYSICS FOR SCIENTISTS AND ENGINEER
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