Question

Galileo Galilei proves the Copernican Heliocentric theory true via certain discoveries and experiments, what are them? What is Newton’s law of universal gravitation? What is Inverse-square law? How to calculate them? Write Newton’s three laws of motion with examples. How to calculate weight in newtons. What are Wien's displacement law and its calculations? The Doppler Effect and its calculations? What is the Proton-proton chain reaction? What kind of object is a star? The properties of neutrinos. Solar neutrinos. And the composition of subatomic particles: proton and neutron.

Answer 1

Galileo used his mathematics knowledge and technical skills to improve upon the spyglass and build a telescope. Later that same year, he became the first person to look at the Moon through a telescope and make his first astronomy discovery. He found that the Moon was not smooth, but mountainous and pitted - just like the Earth! He subsequently used his newly invented telescope to discover four of the moons circling Jupiter, to study Saturn, to observe the phases of Venus, and to study sunspots on the Sun.

Galileo's observations strengthened his belief in Copernicus' theory that Earth and all other planets revolve around the Sun.

Newton's law of gravitation states that the Gravitational force of attraction acting on an object of mass M1 due to mass M2 separated by a distance r is proportional to the product of the two masses and inversely proportional to the square of the distance between them . It is mathematically given by F=G*M1 *M2 / r^2
where F stands for force, G for Universal Gravitational constant, M1 and M2 are the masses of the two object and r is the distance between the two.

In physics,there are certain quantities whose magnitude is inversely proportional to the square of the distance from them.e.g Gravitational force,Electrostatic force, intensity of sound and light etc...These obey the inverse square law.

These laws are found empirically by performing experiments and plotting the data on graph .For example we want to see the dependence of the intensity of light by a light source to the distance of screen from it.So we take a source such as a light bulb and a detector screen that measures intensity of light.We fix the source at a location and measure intensity at varying distances from the screen .We then plot the intensity on the y axis and 1/(r^2) on the x axis.We will see that this gives a straight line,which proves the inverse square law.

Newton's 1st law -  

In an inertial frame of reference,

Every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force.E.g If we roll a ball on a perfectly smooth surface i.e no friction,then the ball will roll indefinitely with uniform speed in the same direction unless stopped .

Newton's second law -

In an inertial frame of reference,

The rate of change of momentum of a body is directly proportional to the force applied and the change in momentum takes place in the direction in which the force is applied.E.g If we apply more force on a ball then it will accelerate more.

Newton's third law -

To every action there is always an equal and opposite reaction.E.g When we jump we apply force on the ground and the ground pushes us with the same force in the opposite direction.

The weight of a body is measured by a spring balance .

Weight = M*g

M - Mass of the body

g - acceleration due to gravity.

Wien's displacement law states that the black-body radiation curve for different temperatures will peak at different wavelengths that are inversely proportional to the temperature.

peak=b/T,
where T is the absolute temperature. b is a constant of proportionality called Wien's displacement constant, equal to 2.897771955...×10^−3 m⋅K.

Doppler Effect refers to the change in wave frequency during the relative motion between a wave source and its observer. It was discovered by Christian Johann Doppler who described it as the process of increase or decrease of starlight that depends on the relative movement of the star.

The above figure shows the proton proton chain reaction that occurs in stars.

A star is an astronomical object consisting of a luminous spheroid of plasma held together by its own gravity. The nearest star to Earth is the Sun.

Properties of neutrino

-They have a very low mass.

Composition-Elementary particle
Statistics- Fermionic
Generation- First, second and third
Interactions - Weak interaction and gravitation
Symbol - νe, νμ, ντ, νe, νμ, ντ
Antiparticle-Opposite chirality from particle.
Types- 3: electron neutrino, muon neutrino, and tau neutrino
Electric charge- 0
Spin - 1/2

Solar neutrinos are exactly what they sound like: neutrinos from the sun. The sun is the source of most of the neutrinos that are passing through you at any moment.
Neutrinos are born during the process of nuclear fusion in the sun. In fusion, protons (the nucleus from the simplest element, hydrogen) fuse together to form a heavier element, helium. This releases neutrinos and energy that will eventually reach Earth as light and heat. All of the neutrinos produced in the sun are electron neutrinos.

Proton is made of three quarks - uud ( up up down ) .

Neutron is made of three quarks - udd (up down down).