CK-12 Physical Science Concepts - For Middle School

2.1. Matter, Mass, and Volume http://www.ck12.org

• The volume of an irregularly shaped solid can be measured by the displacement method. You can read below
  how this method works. For a video on the displacement method, go to this URL: http://www.youtube.com/w
  atch?v=e0geXKxeTn4.

MEDIA

Click image to the left for use the URL below.

URL: http://www.ck12.org/flx/render/embeddedobject/79976

Q:How could you find the volume of air in an otherwise empty room?

A:If the room has a regular shape, you could calculate its volume from its dimensions. For example, the volume of
a rectangular room can be calculated with the formula:

Volume = length×width×height

If the length of the room is 5.0 meters, the width is 3.0 meters, and the height is 2.5 meters, then the volume of the
room is:

Volume = 5.0 m×3.0 m×2.5 m = 37.5 m^3

Q:What is the volume of the dinosaur in the diagram above?

A:The volume of the water alone is 4.8 mL. The volume of the water and dinosaur together is 5.6 mL. Therefore,
the volume of the dinosaur alone is 5.6 mL –4.8 mL = 0.8 mL.

Summary

• Matter is all the “stuff” that exists in the universe. It has both mass and volume.


• Mass measures the amount of matter in a substance or an object. The basic SI unit for mass is the kilogram
  (kg).


• Volume measures the amount of space that a substance or an object takes up. The basic SI unit for volume is
  the cubic meter (m^3 ).