Question 1

Q1: (i) Which one of the following figures represents the age of the earth? (a) 4.6 million years (b) 13.7 billion years (c) 4.6 billion years (d) 13.7 tr...

Accepted Answer

(i) (c) 4.6 billion years Explanation: The source text mentions that the period between 4,600 million years ago and the present led to the evolution of life on the planet. 4,600 million years is equivalent to 4.6 billion years, which represents the approximate age of the Earth. (ii) (b) Differentiat...

Question 2

Q2: (i) What is meant by the process of differentiation? (ii) What was the nature of the earth surface initially? (iii) What were the gases which initiall...

Accepted Answer

(i) What is meant by the process of differentiation? The process of differentiation refers to the separation of the Earth's forming material into different layers based on their densities. During the Earth's primordial stage, it was in a volatile state. Due to immense heat, materials inside started...

Question 3

Q3: (i) Write an explanatory note on the 'Big Bang Theory'. (ii) List the stages in the evolution of the earth and explain each stage in brief.

Accepted Answer

(i) Write an explanatory note on the 'Big Bang Theory'. The Big Bang Theory, also known as the expanding universe hypothesis, is the most popular scientific argument regarding the origin of the universe. In 1920, Edwin Hubble provided evidence that the universe is expanding, meaning galaxies are con...

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