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A block of mass $200$kg is connected to a horizontal ceiling by four identical light elastic ropes, each having natural length $7$m and stiffness $180$N/m. It is also connected to the floor by a single light elastic rope having stiffness $80$N/m. All five ropes are stretched and vertical, and air resistance is neglected.

Find the tension in one of the upper ropes.

I know it's just $kx$, but I don't understand why it is not $\frac{kx}{4}$ because tension is shared between four ropes.

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closed as too localized by Brandon Enright, akhmeteli, Waffle's Crazy Peanut, Qmechanic Jun 17 '13 at 1:34

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1 Answer

This problem can't be answered because it is underconstrained since we have no idea what the tension in the bottom rope is. We know its spring constant, but not enough information was given to know how hard, if at all, that spring is stretched.

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