THERE ARE THREE STAGES OF THE FORMATION OF THE ATMOSPHERE
I .IN THE FIRST STAGE: the early atmosphere consist of hydrogen and helium. loss of primordial atmosphere due to solar winds
II. IN THE SECOND STAGE: Gases were released from the earth’s interior such as Water vapor and other gases. There were water vapor, nitrogen, carbon dioxide methane, ammonia and little free oxygen. The process of outpouring the gases from the interior of the earth is called degassing. Volcanic eruptions contributed the water vapor and CO₂. The CO₂. Disolved in the rainwater and converted into acid rain. Rainwater collected into the depressions called oceans. The oceans were formed about 4000 m y a. The life began to evolve about 3.8 b y a. The photosynthesis evolved about 2500 to 3000 my oceans began to contribute oxygen to the atmosphere. oceans were saturated with oxygen and flooded into the atmosphere.
III IN THIRD STAGE: Living organisms changed the composition of the atmosphere due to photosynthesis

A light-year is defined as the measurement of length or the distance light travels in a vacuum in a year. One light-year is close to 6 trillion miles.

Example of a light-year

• Reflected sunlight travelling from the moon’s surface takes 4.04 × 10^-8 light-years to reach the earth.
• It takes 1.58 × 10^-5 light-years for light from the Sun to reach the earth.

The set of numbers used to describe the position and energy of the electron in an atom are called quantum numbers. There are four quantum numbers, namely, principal, azimuthal, magnetic and spin quantum numbers.

The notion of energy levels and notation has been taken from the atom ‘s earlier Bohr model. Schrodinger ‘s equation evolved the concept from a two-dimensional flat Bohr atom to a three-dimensional model for wave motion. Where n = 1 , 2 , 3 is called the main quantity, and h is the constant of Planck.

The bond order shows the number of chemical bonds present between a pair of atoms. For instance, the bond order of diatomic nitrogen N≡N is 3 and bond order between the carbon atoms in H-H≡C-H is also three. The bond order describes the stability of the bond. The molecular orbital provides an easy understanding of the concept of the bond order of a chemical bond. It quantifies the degree of covalent bonds between the atoms.

 How to calculate Bond order?

The Bond Order Formula can be defined as half of the difference between the number of electrons in bonding orbitals and antibonding orbitals.  
Bond order = 1/2 = N_b - N_a
Where,

N_b is the number of bonding electrons

N_a is the number of antibonding electrons

When Earth formed 4.6 billion years ago from a hot mix of gases and solids, it had almost no atmosphere. The surface was molten. As Earth cooled, an atmosphere formed mainly from gases spewed from volcanoes. It included hydrogen sulfide, methane, and ten to 200 times as much carbon dioxide as today's atmosphere. The atmosphere can be divided into layers based on its temperature. These layers are the troposphere, the stratosphere, the mesosphere and the thermosphere. A further region, beginning about 500 km above the Earth's surface, is called the exosphere. Water vapor, carbon dioxide, methane, ammonia, and other gases similar to the ones produced by volcanoes today were expelled. Over a vast amount of time, millions of years, the earth gradually cooled. ... From these clouds, the oceans formed and the oceans absorbed a lot of the carbon dioxide in the atmosphere.

1. While the terrestrial planets are made of solid surfaces, the jovian planets are made of gaseous surfaces.

2. When comparing the size, the jovian planets are much larger than the terrestrial planets.

3. While the atmosphere of terrestrial planets is composed mainly of carbon dioxide and nitrogen, hydrogen and helium are found in abundance in the atmosphere of jovian planets.

4. The core of the jovian planets is more dense than the terrestrial planets.

5. The jovian planets are far away from the sun.

The leading theory of the Moon's origin is that a Mars-sized body collided with Earth approximately 4.5 billion years ago, and the resulting debris from both Earth and the impactor accumulated to form our natural satellite. The newly formed Moon was in a molten state. The origin of the Moon is usually explained by a Mars-sized body striking the Earth, making a debris ring that eventually collected into a single natural satellite, the Moon, but there are a number of variations on this giant-impact hypothesis, as well as alternative explanations, and research continues into how the Moon came to be. Other proposed scenarios include captured body, fission, formed together (condensation theory, Synestia), planetesimal collisions (formed from asteroid-like bodies), and collision theories.

In our Solar System, astronomers often divide the planets into two groups — the inner planets and the outer planets. The inner planets are closer to the Sun and are smaller and rockier. The outer planets are further away, larger and made up mostly of gas. There are eight planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

The formation of stars are explained below:
(i)The distribution of matter and energy was not even in the early universe. These initial density differences gave rise to differences in gravitational forces and it caused the matter to get drawn together. These formed the base for development of galaxies. 
(iii)Eventually, growing nebula develops localised clumps of gas.These clumps continue to grow into even denser gaseous bodies, giving rise to formation of stars. The formation of stars is believed to have taken place some 5-6 billion years ago.

When earth was first formed, its atmosphere was likely composed of hydrogen, helium, and other gases that contained hydrogen.Over a vast amount of time, millions of years, the earth gradually cooled. When the temperature dropped enough, water vapor condensed and went from a gas to liquid form. This created clouds.

The process through which the gases were outpoured from the interior is called degassing.

Business is considered an economic activity because it is concerned with production, purchase, sale or distribution of goods and Services with an aim of earning profit. An example of activity which is economic in one side and non-economic on other side is teaching. When a teacher teaches in a school, it's an economic activity and when a teacher teaches to his children, it's a non-economic activity.

Dipole Moment Formula

A dipole moment is the product of the magnitude of the charge and the distance between the centers of the positive and negative charges. It is denoted by the Greek letter ‘µ’.

Mathematically,

Dipole Moment (µ) = Charge (Q) * distance of separation (r)

It is measured in Debye units denoted by ‘D’. 1 D = 3.33564 × 10^-30 C.m, where C is Coulomb and m denotes a meter.

The bond dipole moment that arises in a chemical bond between two atoms of different electronegativities can be expressed as follows:

μ = ?.d

Where: μ is the bond dipole moment,

? is the magnitude of the partial charges ?⁺ and ?^–,

And d is the distance between ?⁺ and ?^–.

A substance to which another substance is applied we call it as a substrate. Its definition is different in different sciences. According to biology, it is a medium on which flora, fauna or fungi lives.

Mind affects our stimuli our stimuli affect our nerves our nerves affect our Impulses our impulses affect our signals and our signals affect our reactions that what our behavior . Whenever u see anything u think about it in your mind and react for it that what's your behavior right? . If you see a girl and u start talking hesitantly that wasn't your behavior . it is your feeling . You behaviors ca be seen at public places . You can change your behavior for out of formality but it can represent your feelings right . All that matters is your brain controlling your behavior but its opposite in our daily life. Our mind has to be boss over our body because if our will power gets strong then we will become more powerful . that what we need in our life to live for present only .

Dimension of Velocity is LT⁻¹ 
Dimension of wavelength λ is L 
Dimension of acceleration due to gravity g is LT⁻² 
Dimension of Density of water ρ is ML⁻³
Let v∝λ^ag^bρ^c
Using Dimensional method:
a+b−3c=1  ( Length ) 
c=0 ( Mass ) 
−2b=−1  ( Time ) 
b=0.5 
Hence, a=0.5
∴v∝ √gλ​
v²∝gλ

The kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. 

Consider a body of mass "m" starts moving from rest. After a time interval "t" its velocity becomes V.
If initial velocity of the body is Vi = 0 ,final velocity Vf = V and the displacement of body is "d". Then

Derivation for the equation of Kinetic Energy:
The relation connecting the initial velocity (u) and final velocity (v) of an object moving with a uniform acceleration a, and the displacement, S is 
                             v² - u² = 2aS
This gives  
                             S = ½a(v² - u²) 
We know F = ma. Thus using above equations, we can write the workdone by the force, F as
                            W = ma × ½a(v² - u²) 
                                  or
                             W =m( v 2 - u 2 ) ½

If object is starting from its stationary position, that is, u = 0, then
                            W = ½mv²
It is clear that the work done is equal to the change in the kinetic energy of an object.
If u = 0, the work done will be  W = ½mv²
Thus, the kinetic energy possessed by an object of mass, m and moving with a uniform velocity, v is E_k=  ½mv²