Question map
Not attempted Correct Incorrect ★ Bookmarked
Loading…
Q8 (NDA-I/2008) Science & Technology › Basic Science (Physics, Chemistry, Biology) › Basic mechanics concepts Answer Verified

A rubber ball dropped from 24 m height loses its kinetic energy by 25%. What is the height to which it rebounds?

Result
Your answer: —  Â·  Correct: C
Explanation

When a rubber ball is dropped from a height (h), it possesses initial potential energy (PE = mgh). Upon hitting the ground, this potential energy is converted into kinetic energy (KE). According to the problem, the ball loses 25% of its kinetic energy during the impact [t1, t4]. This means the ball retains 75% of its energy (0.75 * mgh) to rebound [t1, t3]. At the peak of its rebound height (h'), all remaining kinetic energy is converted back into potential energy (mgh'). By equating the remaining energy to the new potential energy (mgh' = 0.75 * mgh), the mass (m) and gravity (g) cancel out, leaving the relationship h' = 0.75 * h [t1, t6]. Given the initial height is 24 m, the rebound height is calculated as 0.75 * 24 = 18 m. The energy loss typically occurs due to inelastic deformation, heat, and sound [t1, t2].

How others answered
Each bar shows the % of students who chose that option. Green bar = correct answer, blue outline = your choice.
Community Performance
Out of everyone who attempted this question.
100%
got it right
✓ Thank you! We'll review this.

SIMILAR QUESTIONS

IAS · 1998 · Q114 Relevance score: -0.76

A ball is dropped from the top of a high building with a constant acceleration of 9.8 m/s2. What will be its velocity after 3 seconds ?

CDS-II · 2022 · Q3 Relevance score: -2.13

An object is dropped from a height onto the floor. Which one of the following remains uniform as it falls?

NDA-I · 2016 · Q12 Relevance score: -2.26

A body has a free fall from a height of 20 m. After falling through a distance of 5 m, the body would

NDA-II · 2016 · Q23 Relevance score: -2.39

A ball is thrown vertically upward from the ground with a speed of 25-2 m/s. The ball will reach the highest point of its journey in

NDA-II · 2016 · Q82 Relevance score: -2.43

Two balls, A and B, are thrown simul¬taneously, A vertically upward with a speed of 20 m/s from the ground and B vertically downward from a height of 40 m with the same speed and along the same line of motion. At what points do the two balls collide by taking acceleration due to gravity as 9-8 m/s*?