Evolution of Earth & Basics

Question 1

Who coined Geography?

Answer 1

Eratosthenes

Question 2

Nebular Hypothesis - Authors and Process

Answer 2

Authors: Immanuel Kant and Later Developed by Pierre Simon Laplace
Process: Cloud of gas and dust (Nebula - dominated by Hydrogen and Helium) contracts under its own gravity forms a spinning disk resulting in planets, moons, and other celestial bodies

Question 3

Planetesimal Theory - Authors and Process

Answer 3

Authors: (CMJH) Chamberlain - Moulton developed and James Jeans - Harold Jeffery supported
Process: Wandering star hit sun and the ejected part evolved into planets

Question 4

Revised Nebular Hypothesis - Authors and Process

Answer 4

Authors: Otto Schmidt and Carl Weizascar
Process: Spinning disk due to collision led to asteroids and they form planets

Question 5

Big Bang Theory - Author and Process

Answer 5

Author: Edwin Hubble
Process: Singularity consisting of infinite temperature and infinite density explodes to form solar system
Phenomenon: Red Shift

Question 6

Planets of the Solar System

Answer 6

Remember: MVEMJSUN
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

Question 7

What are the inner and outer planets?

Answer 7

Inner Planets: MVEM
Outer Planets: JSUN
Differentiated by the Asteroid Belt

Question 8

Variation of Density, thickness of Atmosphere, and Gravity with increasing distance from the Sun (From Mercury to Neptune)

Answer 8

1. Density - Decreases
2. Thickness of Atmosphere - Increases
3. Gravity - Increases

Note: With less gravity for inner planets the gases have escaped easily with the influence of solar wind

Question 9

Inner planets are also known as?
Outer planets are also known as?

Answer 9

1. Terrestrial Planets - Made up of rocks & metals
2. Jovian Planets (Jupiter like)

Question 10

Age of the Sun

Answer 10

5 Billion years

Question 11

Define Solar Cycle

Answer 11

The period in which the sun’s magnetic polarity changes i.e. from N to S and vice - versa

Time Period = 11 years

Question 12

Evolution of Lithosphere

Answer 12

Due to increase in Temperature and Density; the materials inside started getting segregated

The lower dense material flew till crust and higher dense material sunk to the core - Differentiation

Note: With increasing depth - density increases

Question 13

Evolution of Atmosphere and Hydrosphere

Answer 13

Stage - 1: Humongous amounts of H2 and He blew away by solar winds
Stage - 2: Great amount of water vapor converted into precipitation - Degassing

Question 14

When did life and photosynthesis begun?

Answer 14

Life - 3.8B years ago
Photosynthesis - 2.5B - 3B