Published by:
CGP EDU Academic Team
Published on: September 12, 2026
A small body slips, subject to the force of friction, from point A to point B along two curved surfaces of equal radius, first along route 1, then along route 2 (fig.). The friction does not depend on the speed and the coefficient of friction on both routes is the same. In which case will the body’s velocity at B be greater?

Text Solution
Verified by ExpertsThe correct answer is:
A
Step 1: Understanding the Problem
We have a body that moves from point A to point B along two different curved paths with friction acting on it. The coefficient of friction is constant for both paths, and the radii of the paths are equal. We need to determine which path allows the body to reach point B with a greater velocity.
Step 2: Analyzing Forces and Motion
As the body moves along the curved surfaces, it experiences gravitational force, normal force, and frictional force. The gravitational potential energy (PE) lost while descending translates into kinetic energy (KE), but some energy is also converted into heat due to friction.
Step 3: Energy Considerations
Let's denote:
- Mass of the body = m
- Height of point A = h
- Frictional force = f = μN (where μ is the coefficient of friction and N is the normal force)
The gravitational potential energy lost when the body descends to point B is given by:
$$ PE = mgh $$
This is converted partly into kinetic energy (KE) and partly lost to friction:
$$ KE = PE - ext{Friction Energy} $$
Step 4: Path Comparison
For path 1, the body might maintain more consistent acceleration due to a smoother gradient at different heights, while path 2 may involve more abrupt changes in trajectory which can create greater normal forces and, subsequently, friction. Hence, it can be inferred that energy losses due to friction will be higher in the path with a more complicated curve.
Step 5: Conclusion
Thus, the body will have greater velocity at point B when taking the more gently sloped route (path 1). Therefore, the answer is option A.
We have a body that moves from point A to point B along two different curved paths with friction acting on it. The coefficient of friction is constant for both paths, and the radii of the paths are equal. We need to determine which path allows the body to reach point B with a greater velocity.
Step 2: Analyzing Forces and Motion
As the body moves along the curved surfaces, it experiences gravitational force, normal force, and frictional force. The gravitational potential energy (PE) lost while descending translates into kinetic energy (KE), but some energy is also converted into heat due to friction.
Step 3: Energy Considerations
Let's denote:
- Mass of the body = m
- Height of point A = h
- Frictional force = f = μN (where μ is the coefficient of friction and N is the normal force)
The gravitational potential energy lost when the body descends to point B is given by:
$$ PE = mgh $$
This is converted partly into kinetic energy (KE) and partly lost to friction:
$$ KE = PE - ext{Friction Energy} $$
Step 4: Path Comparison
For path 1, the body might maintain more consistent acceleration due to a smoother gradient at different heights, while path 2 may involve more abrupt changes in trajectory which can create greater normal forces and, subsequently, friction. Hence, it can be inferred that energy losses due to friction will be higher in the path with a more complicated curve.
Step 5: Conclusion
Thus, the body will have greater velocity at point B when taking the more gently sloped route (path 1). Therefore, the answer is option A.
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.
Similar Questions
Explore conceptually related problems
A man swings a stone tied to a string of length in a vertical plane. The string remains stretched …
The driver of a car traveling at velocity v suddenly sees a broad wall in front of him at distance …
To anticipate the dip and hump in the road the driver of a car applies her brakes to produce a unif…
A certain rocket maintains a horizontal attitude of its axis during the powered phase of its fligh…
The turning of a car must be produced by an external force acting at an angle to the line of motion…
A body slips down a chute which is in the form of a loop as in fig. It starts from the lowest admis…