1997 General Studies, all questions

UPSC Prelims 1997 · General Studies

Question 115: Science and Technology

Which one of the following has the highest fuel value?

aHydrogen
bCharcoal
cNatural Gas
dGasoline

AnswerThe answer is (a).

Fuel value is the heat given out per unit mass. Hydrogen gives the most, about 120 to 150 MJ per kg, which is two to three times that of natural gas or petrol. Gasoline, natural gas and charcoal give less per kilogram.

Why each option is right or wrong
  • (a) Right: hydrogen has the highest fuel value per kilogram.
  • (b) Charcoal gives about 30 MJ per kg, well below hydrogen.
  • (c) Natural gas gives about 50 MJ per kg, less than half of hydrogen's.
  • (d) Gasoline gives about 45 MJ per kg, about a third of hydrogen's.

Explanation: written by UPSC Grade, not by UPSC.

Practise this paper timedPrevious questionNext question

Source: UPSC, Civil Services (Preliminary) Examination 1997, General Studies. UPSC's own paper isn't online; the words are from a published compilation. The paper on upsc.gov.in.