Work Energy And Power Question 9
Question: Assertion : Comets move around the sun in elliptical orbits. The gravitational force on the comet due to sun is not normal to the comet?s velocity but the work done by the gravitational force over every complete orbit of the comet is zero. Reason : Gravitational force is a non conservative force.
Options:
A) If both assertion and reason are true and the reason is the correct explanation of the assertion.
B) If both assertion and reason are true but reason is not the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason both are false.
E) If assertion is false but reason is true.
Show Answer
Answer:
Correct Answer: C
Solution:
The gravitational force on the comet due to the sun is a conservative force. Since the work done by a conservative force over a closed path is always zero (irrespective of the nature of path), the work done by the gravitational forces over every complete orbit of the comet is zero.
