Doctor Who Wallpapers News

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How it works

waves, sound, and light

Light and sound are two of the most important forms of energy to humans. People see light and hear sound. Light from the Sun makes life on Earth possible. Sound is one of the most important ways that animals and humans communicate. Both sound and light travel as waves. Light also behaves like a partic... read more

heat

Heat is a form of energy. It is created when molecules (small pieces) in an object move around. The study of heat and how it is used is called thermodynamics. Heat is very important to life on Earth. The Sun warms our planet and helps create weather. Heat from our bodies helps them work properly. ... read more

the environment in danger

Everything on Earth is connected in some way. Changes on land can affect the air. Changes in the air can affect the water. Damage to one thing always affects something else. It is easy to damage the Earth. Our planet’s population continues to grow. More people means we need to produce more food and ... read more

why do toucans have such big beaks

Toucans have large beaks in order to regulate their body temperature. ... read more

types of animals

There are many different animals in the world. Animals may eat plants or meat to live. They live in different types of environments all around the world. Their bodies help them to survive in their habitat. ... read more