Question 1

Who postulated the nebular hypothesis regarding the origin of the earth?

Accepted Answer

The nebular hypothesis was initially proposed by Immanuel Kant and later revised by mathematician Laplace in 1796. It considers that the planets were formed out of a cloud of material associated with a youthful sun, which was slowly rotating.

Question 2

Which of the following is considered a modern theory regarding the origin of the universe?

Accepted Answer

The Big Bang Theory, also called expanding universe hypothesis, is the most accepted modern theory regarding the origin of the universe, proposed by Edwin Hubble in 1920.

Question 3

Approximately how old is the planet Earth?

Accepted Answer

Scientific measurements indicate that the earth is approximately 4.6 billion years old. This has been determined using radiometric dating techniques on rocks and meteorites.

Question 4

What is a light-year a measure of?

Accepted Answer

A light-year is a measure of distance, not time. It is the distance that a beam of light travels in one year at the speed of 300,000 km/s.

Question 5

According to the Big Bang theory, when did the event of the big bang take place?

Accepted Answer

The Big Bang event took place approximately 13.7 billion years before the present, marking the origin and rapid expansion of the universe.

The Origin and Evolution of the Earth — CBSE Class 11 Geography Important Questions & Revision Notes