Concept explainers
Work is done when
- a. a force is applied.
- b. a person tries unsuccessfully to move a crate.
- c. force is applied and an object is moved.
The correct option for the work done.
Answer to Problem 1RQ
The correct option is “c. force is applied and an object is moved”.
Explanation of Solution
The object can move from one place to another by applying the constant force which is known as the work done.
Write the expression for the work done as given below:
Here
From Equation (1), the work is related to the displacement of an object when a force is applied to it. Therefore, ‘c’ is the correct option.
In option ‘a’, the force is applied, yet there is no movement of an object. Therefore, option ‘a’ is incorrect.
In option ‘b’, the force is applied, yet a person cannot successfully move a crate. Therefore, option ‘b’ is incorrect.
Conclusion:
Hence, the option ‘c’ is correct and the remaining options are incorrect.
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