## anonymous 3 years ago I know others may have asked this but I just don't understand it as hard as I have tried. I have gone through the solution and it still isn't gelling An ideal (non-viscous) liquid with a density of ! is poured into a cylindrical vessel with a cross-sectional area of A1 to a level at a height h from the bottom. The bottom has an opening with a cross-sectional area A2 . Find the time it takes the k=liquid to flow out. I don't understand what b is or necessarily why v=0 x=-1/2. Thanks in advance

1. anonymous

v=0 relative to the liquid flowing at the bottom. !!Processing error!! There is no specified b or x in your question.

2. anonymous

I don't understand what you mean v=0 relative to the liquid flowing at the bottom. and let me recopy the question my apologies. An ideal (non-viscous) liquid with a density of rho is poured into a cylindrical vessel with a cross-sectional area of A1 to a level at a height h from the bottom. The bottom has an opening with a cross-sectional area A2. Find the time it takes the k=liquid to flow out

according to the continuity of the liquid, $$A_1v_1=A_2v_2$$ v_1 is the velocity of the fluid in A_1 and v_2 is the velocity of the fluid at A_2 section. $$v_1=\frac{A_2}{A_1}v_2$$ Normally in these kind of problems the hole at the bottom is very smaller than the cross sectional area at the higher level thus makes A_2/A_1 is considerably small. So with respect to v_2, v_1 is negligible. So we take v_1=0

4. anonymous

What do you mean by the continuity of the liquid?

5. anonymous

he meant the equation of continuity of fluids. while the question does not say it, the liquid is definitely not flowing into the vessel as it was poured in as that would mean that the fluid is not flowing from A1 to A2. So the liquid should be kept until it has reached the level of height and area A1 before letting it flow. As such, the v1 is zero as it is at first stationary.