Chapter 1 WHat Is HEat Heat is important for all animals and plants Without any heat living things die The same thing happens if living things get too much heat But with the right amount of heat animals and plants live and grow Heat from the sun helps keep living things healthy If a plant gets too hot or too cold it dies But the right amount of heat helps plants grow What do we call the amount of heat an object has 4
Heat is a form of energy The amount of heat an object has is called its temperature Water turns into ice at a temperature called the freezing point Water turns into a gas at a temperature called the boiling point This desert is very hot in the daytime Most plants and animals can’t live there because it is too hot and too dry 5
Measuring temperature We measure temperature in units called degrees Thermometers are tools that are used to measure temperature This thermometer shows the temperature on a warm summer day 6
Some thermometers measure temperature with the Fahrenheit scale Using this scale the temperature at which water freezes is about 32 F 0 C And water boils at about 212 F 100 C Many people in the United States use the Fahrenheit scale Other thermometers measure temperature with the Celsius scale Using this scale water freezes at about 0 C 32 F And water boils at about 100 C 212 F Scientists use the Celsius scale So do most other people around the world TEMPERATURE SCALES 212ºF water boils 100ºC 32ºF water freezes 0ºC Fahrenheit scale Celsius scale ºF stands for degrees Fahrenheit and ºC stands for degrees Celsius 7
