ExamBro
ExamBro
JEE Mains · Physics · STD 11 - Work,energy,power and collision
  • JEE Mains 2024
  • Hard
  • MCQ

If a rubber ball falls from a height \(h\) and rebounds upto the height of \(h / 2\). The percentage loss of total energy of the initial system as well as velocity ball before it strikes the ground, respectively, are _______.

Pick an option to check your answer.
Verified Solution

Answer & Solution

Correct Answer

(D) \(50 \%, \sqrt{2 \mathrm{gh}}\)

Step-by-step Solution

Detailed explanation

\(\text { Velocity just before collision }=\sqrt{2 \mathrm{gh}}\)

\(\text { Velocity just after collision }=\sqrt{2 \mathrm{~g}\left(\frac{\mathrm{h}}{2}\right)}\)

\(\therefore \Delta \mathrm{KE}=\frac{1}{2} \mathrm{~m}(2 \mathrm{gh})-\frac{1}{2} \mathrm{mgh}\)

\(=\frac{1}{2} \mathrm{mgh}\)

\(\therefore \% \text { loss in energy }\)

\(=\frac{\Delta \mathrm{KE}}{\mathrm{KE}_{\mathrm{i}}} \times 100=\frac{\frac{1}{2} \mathrm{mgh}}{\frac{1}{2} \mathrm{mg} 2 \mathrm{~h}} \times 100=50 \%\)

Hence option \((4)\)

Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app