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Question
Coal is said to be formed from the wood of trees. Why then is coal considered to be a non-renewable source of energy whereas wood is a renewable source of energy?
Solution
Coal is classified as a non-renewable source of energy because, when trees die and are buried in the earth, they take many years to decompose and form coal. So, they are not easily available. But wood will continue to be available to us if we use it properly as per a plan.
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