Question

Nicky collected two different types of fuels A and B. She wants to find out which fuel is the most efficient among the fuels she has collected. She burns 6 kg of A and 8 kg of B completely. She found out that the heat produced by complete burning of A and B is 3600 kJ and 4000 kJ respectively. Which of the following are true regarding fuel efficiency and calorific value of the fuels A and B ?

• A. Fuel efficiency of A is more than B
• B. Fuel efficiency of A is less than B
• C. Calorific value of A is more than B
• D. Calorific value of A is less than B

Answer 1

Answer: (A), (C)

The correct options are
A Fuel efficiency of A is more than B
C Calorific value of A is more than B

$\bullet$ The higher the calorific value of fuel, the higher will be the fuel efficiency of that fuel.
$\bullet$ The calorific value of fuel is the amount of heat energy produced by complete combustion of 1 kg of fuel.
$\bullet$ For fuel A: 6 kg of A produces 3600 kJ of heat. 1Kg of A will produce $\frac{3600}{6}=600$
$\therefore$ Calorific value of A is 600 KJ/Kg.
$\bullet$ For fuel B: 8 kg of A produces 4000 kJ of heat. 1Kg of B will produce $\frac{4000}{8}=500$
$\therefore$ Calorific value of B is 500 KJ/Kg.