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about how long will it take to fill a cylinder with a radius of 50cm, & a height 60cm halfway?

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4 Answers

Hi Sophia;
V=(3.14)(r2)(h)
3.14 is pie
Since this is "halfway"...
V=(0.5)(3.14)(50 cm)2(60 cm)
V=235500 cc
1000 cc = 1 liter
(1 liter/1000 cc)(235500 cc)
Let's cancel units where appropriate...
(1 liter/1000 cc)(235500 cc)
235.5 liters
 
The flow is 12.3 liters/minute.
We need minutes/liters.
(1)/(12.3 liters/minute)=0.08 minutes/liter
(235.5 liters)(0.08 minutes/liter)
Let's cancel units where appropriate...
(235.5 liters)(0.08 minutes/liter)
18.84 minutes
Volume of cylinder = [(pi)r2 x height] = 471,238.898 cm3 or 471,238.898 mL or 471,238.898 cc
 
Since we are only filling the cylinder halfway, the volume in which we are interested is half of the volume calculated above, i.e. 235,619.449 cm3 or 235,619.449 cc
 
Water is flowing into the cylinder at a rate of 12.3 L/min or 12,300 cc/min.
 
[(235,619.449 cc)/(12,300 cc-min-1)] = 19.156 minutes
 
 
V=pi*(r^2)*h (volume of a cylinder)
  =3.14159*(50^2)*30, (30 is half of 60 and we fill the cylinder half full)
  =3.14159*2500*30
  =3.14159*75,000
  =235,619.25 cubic cm
  l liter=1000 ml and 1 ml=1 cubic cm
    235,619.25/1000=235.61925 liters
the flow is 12.3 liters per minute
   235.61925/12.3=19.156 minutes
answer: 19.156 minutes
 
By the way, why does l ml=1 cc ?
a liter is a cubic decimeter, a cube 1 dm by 1 dm  by 1 dm or 10 cm by 10 cm by 10 cm whose volume is 10^3 or 1000 cubic cm
but a liter is 1000 ml, so 1000 ml=1000 cc, and therefore 1 ml=1cc (cc=cubic centimeter and
ml=milliliter)(also note that milli means 1/1000)
Be sure to keep your significant figures.  There's a huge difference between answers but all with the right approach.  My answer came to 19.2 minutes.

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