2002 General Studies, all questions
UPSC Prelims 2002 · General Studies
Question 27: Geography
Which one of the following statements is correct with reference to our solar system?
aThe Earth is the densest of all the planets in our solar system
bThe predominant element in the composition of Earth is silicon
cThe Sun contains 75 % of the mass of the solar system
dThe diameter of the Sun is 190 times that of the Earth
AnswerThe answer is (a).
Earth is the densest planet in the solar system, at about 5.5 g/cm3, just above Mercury. The other statements fail: iron is the most abundant element by mass in the whole Earth, with oxygen and silicon next; the Sun holds over 99 percent of the solar system's mass; and the Sun's diameter is about 109 times the Earth's.
Why each option is right or wrong
- (a) Right: Earth's density, about 5.5 g/cm3, is the highest of all planets.
- (b) Iron, not silicon, is the most abundant element by mass in the whole Earth.
- (c) The Sun holds well over 99 percent of the system's mass, not 75 percent.
- (d) The Sun's diameter is about 109 times that of the Earth, not 190.
Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2002, General Studies. UPSC's own paper isn't online; the words are from a published compilation. The paper on upsc.gov.in.