a small city wants to build a cylindrical water tank that holds 10,000,000 liters the city wants the height of the tank to be 10 meters what will be the tanks d

Question

please help tried my best i would appreciate it please 

Answer 1

V = pi(r²)(h) & h = 10 m.

1 liter = 1000 cu cm = 1000 (0.01m)³ = 10^-3 cu m.

V = 10⁷ liters = 10⁴ cu m = pi (r²)(10) cu m.

 

10³ = pi(r²)...now solve for radius of the tank.

Answer 2

Hello Earvin,

 

You'll need three bits of information to solve this problem.

 

First, the volume of a cylinder is

 

     V = πr²h,

 

where r is the radius of the cylinder's base and h is the height of the cylinder.

 

Second, we need to know how to convert Liters to cubic meters:

 

     1m³ = 1000L.

 

Third, we need to remember that the radius of a circle is related to its diameter by:

 

     d = 2r.

 

With these three tools, we're ready to solve this problem. Let's begin by solving the volume equation for r:

 

     r² = V/(πh)

     r = √[V/(πh)]

 

We'll multiply both sides of this equation by 2:

 

     2r = 2√[V/(πh)]

 

Replace 2r with d:

 

     d = 2√[V/(πh)]

 

Before plugging in numbers, let's convert the volume they give us from Liters to cubic meters:

 

     V = 10,000,000L x (1m³/1,000L) = 10,000m³

 

And now we can plug in numbers to calculate the water tank's diameter d:

 

     d = 2√[10,000m³/(3.14159 x 10m)]

     d = 2√[1,000/3.14159 m²]

     d = 35.6825 m.

 

So, we're looking at a fairly squat cylindrical water tank, about 3.5 times wider than it is high.

 

By the way, have you ever gone hiking and spotted those squat, circular buildings up in the hills?

 

Yep. Those are water tanks. :)