Volume

Madam Vidya walks in and says, "Please keep your bags on your seats and sit down." The students cannot sit! The bags have taken up the space on the seats. Everything takes up some space.

She gives two students two identical glass tumblers. Each pours the water left in their bottle into a tumbler. One tumbler is half full; the other is almost full. The water in the half-full tumbler takes up less space: it has less volume. The space taken up by something is its volume. (Not the volume knob on a TV!)

Volume is measured in litres (L) and millilitres (mL). Look at bottles of water or milk: 1 L, 500 mL, 200 mL. These numbers tell you the volume of liquid inside.

The SI unit of volume is the cubic metre, written m³, and 1 m³ = 1000 L.

Writing volume correctly:

• Litre is written with a capital L.
• Millilitre is written mL: small m, capital L, no space between them.
• A space between the number and the unit: 500 mL, 2 m³.