ENERGY PROFESSIONAL ENGLISH IN USE FOR ENGINEERING

 

PROFESSIONAL ENGLISH IN USE FOR ENGINEERING UNIT 35. ENERGY

 

A Forms of energy The effects of energy can be seen, felt or heard in different ways, depending on the form of energy question. The main forms are listed below: ·       kinetic energy: energy in the form of movement – a type of mechanical energy ·       thermal energy: energy in the form of heat ·       electrical energy: the energy of an electric current ·       sound energy: energy in the form of noise B Energy efficiency Machines of often convert an energy source, such as electricity, to another form of useful energy – in other words, energy used for a purpose. For example, a motor converts electrical energy (the energy source) into kinetic energy (useful energy). But it also converts some energy into heat and noise. As this will be anticipated into the air, and not used, it is waste energy. C Work and power The amount of energy needed to do a task – for example, lifting a load to certain height by crane – is called work. The amount of energy converted in order to perform tasks – in other words, the amount of work done – is measured in joules (J). if a force of one newton is required to keep an object moving, the work required to move that object over a distance of one metre is equal to one joule. EXERCISES 35.1 Make word combinations with energy using words from A and B opposite. Then match the combinations with the descriptions (1-8). 1. ________________ energy = energy stored within the liquids or solids in a battery. 2. ________________ energy = mechanical energy in the form of movement. 3. ________________ energy =potential energy stored in a deformed material 35.2 Complete the article about electric and diesel-electric locomotives using the words in the box. Look at A, B and C opposite to help you. chemical efficiency form kinetic powerful thermal wattage convert efficient gain power source useful work dissipated electrical joules powered stored waste     An electric locomotive is one that is (1)_________ by an external energy (2)_________, most often via overhead electric lines. This differs from a diesel-electric locomotive, which has an onboard fuel tank and a diesel-powered generator to provide electricity for its motors. Purely electric power has numerous advantages over diesel-electric power, explaining the choice of electric locomotives for use in high-speed trains.

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