Volume of a cylinder

Posted on by Schuyler

A battery in the shape of a perfect cylinder has a volume of 15 cm³. Its height is 6 cm. Find the radius of the battery.

cylinder

h= 6 cm

volume= 15 cm³

We know the formula for the volume of a cylinder is:

h\pi { r }^{ 2 }

where r=radius and h=height

So, 15=6\pi { r }^{ 2 }, then we divide both sides by 6. \frac { 15 }{ 6\pi } =\frac { 6\pi }{ 6\pi } { r }^{ 2 }

This simplifies to: .7958={ r }^{ 2 }. Taking the square root of both sides gives us: .89={ r }. In other words, the radius of the battery is a little less than one centimeter.