Direction: In the following questions, a statement of assertion is fo...
Work done by the gravitational force in moving a body through a certain distance remains the same whether the body moves uniformly or with decreasing acceleration.It is correct statement.
Gravitational forces are conservative forces.It is correct statement But reason is not correct explanation of assertion.
View all questions of this test
Direction: In the following questions, a statement of assertion is fo...
Assertion: Work done by the gravitational force through a certain distance is constant irrespective of the fact that the body has a uniform or accelerated motion.
Reason: Gravitational force is a conservative force.
Explanation:
- Work done by a force is given by the product of the force and the displacement of the object in the direction of the force.
- The formula for work done is given by W = F * d * cosθ, where W is the work done, F is the force, d is the displacement, and θ is the angle between the force and displacement vectors.
- In the case of gravitational force, the work done is given by W = m * g * h, where m is the mass of the object, g is the acceleration due to gravity, and h is the height or displacement in the vertical direction.
- The work done by the gravitational force is independent of the path taken by the object. It only depends on the initial and final positions of the object.
- This is because gravitational force is a conservative force, which means the work done by the force is path independent.
- The work done by a conservative force only depends on the initial and final positions of the object and not on the path taken.
- In the case of uniform motion, the work done by the gravitational force is constant as long as the object moves along a vertical line.
- In the case of accelerated motion, the work done by the gravitational force is also constant as long as the object moves along a vertical line.
- Therefore, the assertion is true. The work done by the gravitational force through a certain distance is constant irrespective of the fact that the body has a uniform or accelerated motion.
- The reason given is also true. Gravitational force is indeed a conservative force.
- However, the reason does not provide a correct explanation for the assertion. The reason talks about the path independence of the work done by a conservative force, but it does not directly explain why the work done by the gravitational force is constant in both uniform and accelerated motion.
- Therefore, the correct answer is option B. Both the assertion and reason are true, but the reason is not the correct explanation of the assertion.
To make sure you are not studying endlessly, EduRev has designed Class 9 study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Class 9.