Home Physics Motion in a Plane Circular Motion in Vertical Plane A body of mass 100 g is rotating in a circul…
Physics Motion in a Plane Circular Motion in Vertical Plane Single Correct MCQ
Published on: September 12, 2026

A body of mass 100 g is rotating in a circular path of radius r with constant speed. The work done in one complete revolution is.

A
100 rJ
B
(r/100) J
C
(100/r) J
D
Zero

Share this question

For Instagram sharing, use “Apps” on mobile or copy the link.

Text Solution

Verified by Experts
The correct answer is:
D
Step 1: Understand what work done means in a circular motion. In circular motion, the direction of the velocity of the body is continuously changing, while its speed remains constant.

Step 2: Work done is defined mathematically as the dot product of force and displacement:
$$W = F imes d imes ext{cos}( heta)$$ where $F$ is the force exerted, $d$ is the displacement, and $ heta$ is the angle between the force and displacement vectors.

Step 3: In uniform circular motion, the centripetal force acts towards the center of the circular path. The displacement in one complete revolution is along the circular path, which is perpendicular to the centripetal force.

Step 4: Because the angle between the centripetal force and the displacement vector is 90 degrees, the cosine term becomes zero:
$$ ext{cos}(90^ ext{o}) = 0$$.

Step 5: Thus, the work done in one complete revolution is:
$$W = F imes d imes 0 = 0$$.

Conclusion: Therefore, the work done in one complete revolution is zero.

Prepare Smarter with CGP Edu

Get practice questions, solutions, and test series in one place.

Write a Review

Share your experience with this question and solution.

Commentary

Send your comment, doubt, correction, or feedback to admin.

Student Reviews

What students say about this solution

No reviews yet. Be the first to write a review.

Similar Questions

Explore conceptually related problems

CG
CGP Question Assistant Question Bank + AI Help
Hi! Type your question or upload one screenshot. First I will search related questions from CGP Edu Question Bank. If none match, type YES and I will solve it with AI.
Upload only one screenshot at a time. Flow: Question Bank first → If not matched, type YES for AI solution.