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Question
What should be the characteristic of a source of energy?
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Solution
A good source of energy should have the following characteristics:
(i) It should do a large amount of work per unit mass or volume.
(ii) It should have a high calorific value.
(iii) It should be easily accessible over a long period of time.
(iv) It should be economical and easy to store and transport.
(v) It should be safe and convenient to use.
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Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
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