Class 12th Biology 2012 Set1 Delhi Board Paper Solution
Question 26
By the end of 2002 the public transport of Delhi switched over to a new fuel. Name the fuel. Why is this fuel considered better? Explain.
Answer
Delhi had been categorized as the fourth most polluted city of the world in a list of 41 cities. Burning of fossil fuels has added to the pollution of air in Delhi. So, in year 2002 it switched over to new fuel - CNG (COMPRESSED NATURAL GAS).
It is considered better due to following reasons
CNG is a clean fuel that produces very little unburnt particles and thus it is considered as eco friendly. CNG burns most efficiently, unlike petrol or diesel, in the automobiles and very little of it is left unburnt. Moreover, CNG is cheaper than petrol or diesel, cannot be siphoned off by thieves and adulterated like petrol or diesel.Popular Questions of Class 12th biology
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