JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A block of mass ' \(m\) ' (as shown in figure) moving with kinetic energy \(E\) compresses a spring through a distance \(25\,cm\) when, its speed is halved. The value of spring constant of used spring will be \(nE\; Nm ^{-1}\) for \(n=\)
- A \(26\)
- B \(12\)
- C \(23\)
- D \(24\)
Answer & Solution
Correct Answer
(D) \(24\)
Step-by-step Solution
Detailed explanation
Using work - energy theorem \(W _{\text {net }}=\left( K _{ f }- K _{ i }\right)\) \(\Rightarrow-\frac{1}{2} Kx ^{2}=\frac{1}{2} m \left(\frac{ v }{2}\right)^{2}-\frac{1}{2} mv ^{2}=\frac{ E }{4}- E\)…
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