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The nature of energy Energy can exist in different forms. Look at the list of energy forms below and try to find examples of each. Energy type Thermal light sound elastic gravitational Kinetic electrical chemical nuclear Examples

Here are some answers: Energy type Examples Thermal hot water, a hot radiator Light light bulbs, Bunsen flame Sound talking, TV, radio Elastic a door closer, clockwork toys Gravitational a book on a high shelf, a flying ball Kinetic anything that is moving Electrical anything electrical Chemical food, batteries, burning things Nuclear nuclear bombs, and power stations

The nature of energy Energy can be changed from one form to another. Examples: What other energy transfers can you think of? Chemical energy in food is converted to thermal energy and kinetic energy by our bodies. Gravitational energy in a ball is converted to kinetic energy when it falls to the ground.

In all these transfers, energy is conserved. Suggest the energy transfer for the devices below: chemical to heat and light sound to electrical electrical to sound and heat electrical to sound and light and heat elastic to kinetic and heat chemical to sound and microwaves (EM radiation) and heat chemical to kinetic & sound & heat A match burning A portable torch A microphone A radio A TV A catapult A mobile phone A car Click for answers In all these transfers, energy is conserved. Energy cannot be destroyed or created.

Energy Resources We all use chemical energy (food) to live and function. However, in a modern society we also use large amounts of energy from other sources. Think of some activities requiring energy: We travel and communicate over long distances. We control our environment - air conditioning / heating We manufacture and build many kinds of materials and things – e.g. roads, cars, buildings, prepared food The pie diagram next shows where the energy comes from for some of theses activities.

Energy Supplies in Britain These energy resources can be divided into two types: renewable and non-renewable.

Non-renewable Energy sources Oil Coal Natural gas Oil, coal and natural gas are examples of fossil fuels. They were formed from biological deposits over the course of millions of years. There is a finite amount of these materials on the Earth so they will run out eventually. Once they are used up they cannot be regenerated and used again.

Renewable Energy sources These will not run out because they can easily be regenerated. Examples are wind power, solar power, tidal power and biomass. Only 1% of the UK’s energy comes from these sources. Can you think of a reason why?

Energy The Sun The original source of most energy resources. Plants store the sun’s energy through photosynthesis. Animals then eat the plants.

The Sun Natural gas Oil The original source of most energy Coal resources. Coal biomass food Wind waves

How coal was formed About 300 million years ago, plants photosynthesized and stored the Sun’s energy. Coal Dead plants fell into swampy water and the mud stopped them from rotting away. Over the years, the mud piled up and squashed the plants. After millions of years under this pressure, the mud became rock and the plants became coal.

Coal Formation

How Oil was formed Oil is also biological in origin. Millions of years ago tiny animals lived in the sea. Like now their ecosystem was dependent on heat and light from the Sun and photosynthesis by plants. When they died they fell into mud and sand at the bottom of the sea but didn’t rot away. Over millions of years, they got buried deeper by the mud and sand. The temperature and pressure (caused by the weight of the sediments and deep burial) changed the mud and sand into rock and the dead animals into crude oil and natural gas. This sample of crude oil was formed in Southern England. Crude oil formed in other parts of the world can be very different in appearance and viscosity.

Oil Formation