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صفحة: 6
Types of Energy Energy is manifested in various natural phenomena and is vital for the operation of machines and devices . Energy does not appear in one uniform form ; rather , it appears in our world in a multitude of forms . There are different types of energy , for example : Kinetic energy This is the energy a body has when moving . For example , a traveling car has kinetic energy . The faster it goes , the more kinetic energy it has . When a car is standing still , it has no kinetic energy . A person walking also has kinetic energy , as does a revolving fan . Questions 1 . Which of the following examples illustrate kinetic energy ? Explain . a . A child sitting on the top of a slide . b . A ball rolling on a soccer field . c . A fan in action . d . Light radiation reaching the earth from the stars . e . The wind blowing . 2 . Suggest other examples that illustrate kinetic energy . Potential energy This is the energy a body has when elevated above a surface ( such as the ground ) . For example , children at the top of a slide have potential energy . When they slide down the slide , they lose the potential energy they have accumulated . A tennis ball raised above the ground has potential energy as well , as does an orange on a tree . Heat This is the energy added to a body when heated or during a change in its state of matter . The energy added to water heating in a kettle , and the energy added to a meteorite as it penetrates the atmosphere , becoming red hot ( a falling star ) are examples of heat .
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