| Introduction Section 1 Matter and Chemicals Atoms Molecules Solids, liquids and gases Melting and boiling Water Dissolving Chemical changes Metals Section 2 Energy,Motion and Machines About energy Converting energy Forces and motion Gravity Heat and cold Simple machines Friction Energy for the world Section 3 Electricity and Magnetism Electrical energy Static electricity Flowi n g electricity Electricity from chemicals Electrical circuits Electricity makes magnetism Mysterious magnetism Communications Section 4 Sound and Light About waves Sound waves High and low sounds Loud and soft sounds Light Reflected light Refracted light Using light Section 5 Earth and Life Inside the Earth Volcanoes and earthquakes At mosphere Weather and climate Rivers and lakes Life on Earth Prehistoric life Earth in trouble …… |
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