Concept explainers
Is it possible for the kinetic energy of an object to be negative? Is it possible for the gravitational potential energy of an object to be negative? Explain.
Answer to Problem 1CQ
Explanation of Solution
Write the expression of kinetic energy of the body.
Here,
Kinetic energy is the product of mass and square of the velocity and mass and the term
Thus, the kinetic energy of an object cannot be negative.
Write the expression of potential energy of the object.
Here,
The datum line can be selected anywhere. If the object is at height
Thus, the potential energy of the object can be negative.
Conclusion:
Therefore, the kinetic energy cannot be negative but potential energy can be negative.
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