GCSE Science

National grid * electrical power is transferred at high voltages from power stations, and then transferred at lower voltages in each locality for domestic use Step-up transformers * increases the voltage * this allows the cables

What is a wave? * Waves are a transfer of energy. What is a transverse wave? * Transverse waves: the vibrations are perpendicular to the direction of the wave (water, EM waves) What is a

Atmospheric gases now * 80% Nitrogen * 20% Oxygen * 0-1% other gases e.g. water vapour, carbon dioxide etc. Early atmosphere * a lot of carbon dioxide and water vapour * very little oxygen Why did oxygen