JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A body of mass \(1\,kg\) falls freely from a height of \(100\,m,\) on a platform of mass \(3\,kg\) which is mounted on a spring having spring constant \(k = 1.25 \times 10^6\, N/m.\) The body sticks to the platform and the spring’s maximum compression is found to be \(x.\) Given that \(g = 10\,ms^{-2},\) the value of \(x\) will be close to ................ \(\mathrm{cm}\)
- A \(40\)
- B \(4\)
- C \(80\)
- D \(2\)
Answer & Solution
Correct Answer
(D) \(2\)
Step-by-step Solution
Detailed explanation
\begin{array}{l} v = \sqrt {2 \times 10} \times 100\\ \,\,\,\, = 20\sqrt 5 \\ COLM \to \,{v_p} = \frac{{1 \times 20\sqrt 5 }}{4}\\ COTME \to \\ \frac{1}{2} \times 4 \times {\left( {5\sqrt 5 } \right)^2} + \frac{1}{2}1.25 \times {10^6}{\left( {\frac{{30}}{k}} \right)^2}…
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