Concept explainers
The work done by the gravitational force during a short interval in which the Earth moves through a displacement in its orbital path.
Answer to Problem 7.1QQ
Option (a) zero.
Explanation of Solution
The Earth revolve around the sun in an orbit and the orbit is perfectly circular.
Formula to calculate the work done by the gravitational force is,
Here,
Since, the Earth moves through a displacement in its orbital path and the orbital path is perfectly circular. So, the total displacement of the Earth in its orbital path is zero.
Substitute
Thus, the work done by the gravitational force during a short interval in which the Earth moves through a displacement in its orbital path is zero.
Conclusion:
The work done by the gravitational force is zero and the option (a) is zero. Thus option (a) is correct.
The work done by the gravitational force is zero but the option (b) is positive. Thus option (b) is incorrect.
The work done by the gravitational force is zero but the option (c) is negative. Thus, option (c) is incorrect.
The work done by the gravitational force is zero. It means the work done can be determined. Thus, option (d) is incorrect.
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Chapter 7 Solutions
Physics For Scientists And Engineers, Volume 2
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