Thermometers — Measuring Temperature

A thermometer measures TEMPERATURE — how hot or cold something is! Inside a glass thermometer is a liquid (usually red-colored alcohol) that expands (gets bigger) when warm and shrinks when cold. As the liquid expands, it rises up the tube. Numbers on the side tell you the temperature. Higher numbers = warmer. Lower numbers = colder. Digital thermometers use electronic sensors but do the same job!