Question

a straw is 25cm long and 8 mm in diameter. How much liquid can be held in the straw at one time? the straw can contain ____ ml of liquid..(type an exact in terms of π)

Answer 1

A straw is cylindrical in nature.

The amount of liquid that a structure can hold is the volume.

Thus, we find the volume of the cylinder.

Given:

All units must be the same, so we convert them to be in the same unit of length.

The volume of a cylinder is given by;

`V=\pi r^2h`
`\begin{gathered} V=\pi*0.4^2*25 \\ V=4\pi cm^3 \end{gathered}`

The volume in terms of pi is

`4\pi cm^3`

To convert the volume to mL,

Therefore,

`4\pi cm^3=4\pi mL`

Therefore, the straw can contain 4 pi mL of liquid.

Volume =

`4\pi\text{ mL}`