universe & solar system section 12 MCQ Questions & Answers Detailed Explanation

Question : 1

What is the primary cause of the day and night ?

a) Inclination of the earth’s axis and its rotation

b) Inclination ofthe earth’s axis and itsrevolution

c) Earth’s daily motion

d) Earth’s annual motion

Question : 2

The principle of Black hole was enunciated by

a) S. Chandrashekhar

b) H. Khurana

c) H.J. Bhabha

d) C.V. Raman

Question : 3

The planet Pluto has been abandoned from the group of the conventional planet and kept in the group of dwarf planet by a summit held in

a) Geneva

b) Prague

c) London

d) Paris

Question : 4

How many kilometres are represented by 1° of latitude?

a) 111 km

b) 91 km

c) 211 km

d) 321 km

Question : 5

Consider the following two statements. One labeled as the Assertion (A) and other as Reason (R). Examine these two statements carefully and select the correct answer by using the codes given below.
Assertion (A):
Existence of human life on Venus is highly improbable.
Reason (R):
Venus has extremely high level of carbon dioxide in its atmosphere.
Codes:

a) A is true, but R is false.

b) A is false, but R is true.

c) Both A and R are true, but R is not the correct explanation of A.

d) Both A and R are true and R is the correct explanation of A.

Question : 6

Consider the following statements:

1. The Axis of the earth’s magnetic field is inclined at 23 and half to the geographic axis of the earth.
2. The earth’s magnetic pole in the Northern Hemisphere is located on a Peninsula in Northern Canada.
3. The earth’s magnetic equator passes through Thumba in South India.

a) 2 only

b) 3 only

c) 2 and 3

d) 1, 2 and 3