-2 should be correct. It is an input for that given graph.
A=1/2ap
(40ft^2)=1/2*8*p
p=(40ft^2)/4
2 1/2 = 2.5
12 1/2 = 12.5
This means you can calculate how may times it goes in by dividing it and rounding the number down:
12.5 / 2.5 = 5
*5 can not be rounded down so it stays the same
This means that 2 1/2 goes into 12 1/2 5 times. Hope this helps! :)
Answer) -5/2 quarts per hour
Work) There are 60 minutes in an hour and the faucet is losing water every 15 minutes so divide 60/15 and you get 4, next you take the 5/8 and times it by the 4 and you get -5/2
Second moment of area about an axis along any diameter in the plane of the cross section (i.e. x-x, y-y) is each equal to (1/4)pi r^4.
The second moment of area about the zz-axis (along the axis of the cylinder) is the sum of the two, namely (1/2)pi r^4.
The derivation is by integration of the following:
int int y^2 dA
over the area of the cross section, and can be found in any book on mechanics of materials.
