The system as shown in the figure is released from rest. The pulley...

The system as shown in the figure is released from rest. The pulley, spring and string are ideal \& friction is absent everywhere. If speed of \( 5 \mathrm{~kg} \) block when \( 2 \mathrm{~kg} \) block leaves the contact with ground is \( 2 \sqrt{x} \mathrm{~m} / \mathrm{s} \), then value of \( x \) is : (spring constant \( k=40 \mathrm{~N} / \mathrm{m} \& g=10 \mathrm{~m} / \mathrm{s}^{2} \) )
\( \mathrm{P} \)
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