Heat (Introduction) class 7

Heat

    What is Energy?
—In science, Energy is the ability to do work.
—Energy can neither be produced nor be destroyed. 
—There are different forms of energy and it can be transformed from one form to another.
                                       
Thermal or Heat energy
—Heat is thermal energy transferred from a hotter system to a cooler system that are in contact.
—It can produce a sensation of hotness or coldness.

Our sense of touch is not reliable to check hotness and coldness
    we cannot always rely on our sense of touch to decide whether an object is hot or cold. Sometimes it may deceive us by misinforming with different feeling about the hotness or coldness of the same object.

What do we mean by the term 'Temperature'? 
—A reliable measure of the hotness or coldness of an object is its temperature.
—Temperature is measured by a device called thermometer. 

 What are the differences between Heat and Temperature?

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