Figure shows four situations in which a red liquid and a gray liquid are in a ∪-tube. In one situation the liquids cannot be in static equilibrium. (a) Which situation is that?

(b) For the other three situations, assume static equilibrium. For each, is the density of the red liquid greater than, less than, or equal to the density of the gray liquid?

Question

Figure shows four situations in which a red liquid and a gray liquid are in a ∪-tube. In one situation the liquids cannot be in static equilibrium. (a) Which situation is that?

(b) For the other three situations, assume static equilibrium. For each, is the density of the red liquid greater than, less than, or equal to the density of the gray liquid?

ganeshie8 · Answer

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kainui · Answer

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It's gotta be 2 that's not in static equilibrium, since there's an unbalanced force acting on it.

3 has to have the same density since if it was grey you wouldn't notice it.

Imagine if red was denser, it would be heavier and push the grey liquid down more to balance like they do in 3, but it doesn't so red is less dense. Similar but opposite argument for 4.