There are 20,000 vehicles operating in a city with an average annual travel of 12,000 km per vehicle

Q. There are 20,000 vehicles operating in a city with an average annual travel of 12,000 km per vehicle. The NOx emission rate is 2.0 g/km per vehicle. The total annual release of NOx will be

(A) 4,80,000 kg          (B) 4,800 kg               (C) 480 kg                  (D) 48 kg

Ans: 4,80,000 kg

Sol:

Total Annual Emission = Average Annual daily emission per vehicle × Number of Vehicle

Average Annual daily emission per vehicle = Emission per km of travel × Distance traveled (in km)

∴ Total Annual Emission = Number of vehicles × Distance travelled × Rate of emission

Calculation:

Total Annual Emission = Number of vehicles × Distance traveled × Rate of emission

∴ Total Annual Emission = 20000 × 12000 × 2 × 10^-3 (kg) = 480000 kg