Coefficient Of Restitution
A rubber ball is dropped from a height of 2 m onto a hard floor and rebounds to a height of 1.28 m after the first bounce. What is the coefficient of restitution between the ball and the floor?
Select the correct option:
🔒 Solution Hidden from View
Submit your answer to unlock the detailed step-by-step solution.
More work, energy and power Practice Questions
A ball is dropped from a height of 4 m and rebounds to a height of 1 m. What is the coefficient of r...
A ball is dropped from a height of 4 m and rebounds to a height of 1 m. What is the coefficient of r...
A satellite moves in a perfectly circular orbit around the Earth under the gravitational pull direct...
A satellite moves in a perfectly circular orbit around the Earth under the gravitational pull direct...
A cyclist of total mass 70 kg rides up a slope inclined at 30 degrees to the horizontal at a steady ...
A cyclist of total mass 70 kg rides up a slope inclined at 30 degrees to the horizontal at a steady ...
A small stone tied to a string is whirled in a vertical circle of radius 2 m. What is the minimum sp...
A small stone tied to a string is whirled in a vertical circle of radius 2 m. What is the minimum sp...
Two bodies of different masses possess the same magnitude of linear momentum while moving in a strai...
Two bodies of different masses possess the same magnitude of linear momentum while moving in a strai...
A ball is thrown vertically upward and returns to the same height from which it was launched on a wi...
A ball is thrown vertically upward and returns to the same height from which it was launched on a wi...
A stone of mass 0.5 kg is dropped from rest at a height of 8 m above the ground. Ignoring air resist...
A stone of mass 0.5 kg is dropped from rest at a height of 8 m above the ground. Ignoring air resist...
A weightlifter raises a barbell of mass 80 kg from the floor to a height of 2 m above the floor in 4...
A weightlifter raises a barbell of mass 80 kg from the floor to a height of 2 m above the floor in 4...
A 2 kg lump of clay moving at 6 m/s strikes and sticks to a 4 kg block initially at rest on a fricti...
A 2 kg lump of clay moving at 6 m/s strikes and sticks to a 4 kg block initially at rest on a fricti...
A car engine delivers a constant power of 50 kW while the car moves at a steady speed of 25 m/s alon...
A car engine delivers a constant power of 50 kW while the car moves at a steady speed of 25 m/s alon...
A wooden crate of mass 10 kg is dragged 5 m up a rough incline by a force, and friction exerts a con...
A wooden crate of mass 10 kg is dragged 5 m up a rough incline by a force, and friction exerts a con...
Which of the following statements correctly distinguishes a conservative force from a non-conservati...
Which of the following statements correctly distinguishes a conservative force from a non-conservati...
About This Question
- Subject
- physics
- Chapter
- work, energy and power
- Topic
- coefficient of restitution
- Difficulty
- Hard
- Year
- 2025
Solution
Correct Answer:
0.8
As discussed in NCERT Class 11, Chapter 6 (Work, Energy and Power), the coefficient of restitution between a falling object and a fixed surface equals the ratio of the rebound speed to the impact speed. Using energy conservation, speed is proportional to the square root of the drop or rebound height, so e = sqrt(h_rebound / h_drop) = sqrt(1.28 / 2) = sqrt(0.64) = 0.8. The coefficient lies between 0 and 1 for a real bounce, with 1 being perfectly elastic. The option 0.64 mistakenly takes the height ratio itself without the square root. The option 0.9 overestimates the bounce. The option 0.5 underestimates it. A plausibility check: the ball loses energy on impact, so the rebound height of 1.28 m is less than the 2 m drop, giving e below 1, and the value 0.8 fits a fairly bouncy but non-ideal rubber ball.
This hard difficulty physics question is from the chapter work, energy and power, covering the topic of coefficient of restitution. It appeared in the 2025 exam.
Looking for more practice? Explore all physics questions or browse work, energy and power questions on RankGuru.