What is meant by the calorific value of a sample of coal is 30,000 kJkg-1?
OR
Why can wind energy be used for sustainable growth development?
WBBSE
Class X
Physical Science
Concerns about our Environment
01 Mark
2023
The calorific value of a sample of coal being 30,000 kJ/kg means that when one kilogram of this coal is completely burned, it releases 30,000 kilojoules of energy in the form of heat.
Wind energy can be used for sustainable growth development because it is a renewable resource.
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