JEE — Spring Connected BlockHardQuestion 30267
Question
Block A (2 kg) and B (3 kg) are connected by a spring. B rests on the floor. A is pressed down compressing the spring by x = 0.1 m (k = 500 N/m). A is released. Does A leave B? (g = 10)
- ANo, never
- BYes, when spring is at natural length
- CYes, when spring is stretched by 0.04 m
- DYes, when spring is stretched by 0.06 mCorrect
Correct answer
Yes, when spring is stretched by 0.06 m
Explanation
B leaves floor when spring tension > Mg_B: kx₀ = m_B×g → x₀ = 3×10/500 = 0.06 m above natural length. A leaves the spring complex scenario, but B leaves floor at 0.06 m extension.