A tank is full of water. Find the work required to pump the water out of the spout. (Use 9.8 m/s2 for g. Use 1000 kg/m3 as the density of water. Assume r = 9 m and h = 3 m.)

Question

amistre64 · Answer

missing some vital information such as shape of the tank and ... well i spose it said full of water and not half or third full

anonymous · Answer

sorry spherical

amistre64 · Answer

murmur ... couldnt be cylindar could it lol; so what does the h refer to then?

anonymous · Answer

attachment

amistre64 · Answer

that clears things up

amistre64 · Answer

we should determine what a typical slice of volume looks like then

amistre64 · Answer

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amistre64 · Answer

i wonder if we want to use trigs in this ... cant tell if itd make it simpler or not

anonymous · Answer

i dont think it will make it simpler

amistre64 · Answer

well, lets define the radius of a disc in terms of y then

R = sqrt(9^2 - (9-y)^2)
   = sqrt(81 - (81 -18y +y^2))
   = sqrt(81 - 81 +18y -y^2)
   = sqrt(18y -y^2)

seems to work for the top half

amistre64 · Answer

whereas:

R = 9 sin(angle) seems pretty simple

anonymous · Answer

whats the angle

amistre64 · Answer

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