JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
Two blocks with masses 100 g and 200 g are attached to the ends of springs A and B as shown in figure. The energy stored in A is E . The energy stored in B , when spring constants \(k _{ A }, k _{ B }\) of A and \(B\), respectively satisfy the relation \(4 k _{ A }=3 k _{ B }\), is :
- A 4E
- B 2E
- C 3E
- D \( \frac{4}{3}E \)
Answer & Solution
Correct Answer
(C) 3E
Step-by-step Solution
Detailed explanation
For equilibrium \( kx=mg \) \( U=\frac{1}{2}kx^{2}=\frac{1}{2}\frac{m^{2}g^{2}}{k} \) \( U\propto\frac{m^{2}}{k} \) \( \frac{U_{A}}{U_{B}}=(\frac{m_{A}}{m_{B}})^{2}\frac{k_{B}}{k_{A}}=(\frac{1}{2})^{2}(\frac{4}{3})=\frac{1}{3} \)…
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