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prajaktadighe

 

 

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My earlier article on ‘Human Evolution’Due to the morphological and anatomical similarities between the apes and humans, scientists believed that the great apes were the closest biological relatives of human beings http://timesofindia.speakingtree.in/public/spiritual-slideshow/seekers/science-of-spirituality/human-evolution-243946/60992 dated 11 nov2013 the process of evolution in humans continues even now.

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It is taking place in a slow pace, thats why we are not able to notice the evolutionary changes. According to Hardy-Weinberg Equilibrium’, changes which take place due to evolution are a mathematical necessity. These changes may get interrupted or influenced only by mutations, natural selection, gene flow, or non-random mating.

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Humans just like any other species are subject to the forces of Nature and are still evolving physically and biologically too.

Cultivation: Cultivation was a major aspect in evolving mankind. Their social life, physical labour and intellect developed largely. The surplus food produced from agriculture secured a stable life from nomadic life and…

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WHAT IS GRAVITY?

What is GRAVITY?g2
In the year 2013 a Science fiction movie GRAVITY was awarded with OSCAR My daughter persuaded us to see this movie on big screen in Cinema Hall to get the 3D effect. It was amazing to see a Medical Engineer Astronaut Dr. Ryan Stone (Actress Sandra Bullock) and a veteran Astronaut Matt Kowalsky (Actor George Clooney) on a space shuttle to repair the damaged Hubble Telescope. During their space walk , disaster strikes their shuttle and other crew members gets destroyed leaving the two astronauts stranded in Space. No link with the Earth, the terrifying expanse of space how they make to International Space Stations and another Chinese Space station close by…
and board a Soyuz model and return home (Earth).A unique grand movie
Everything floats in Space as there is no Gravity there.

Due to this gravity we have a firm foothold on Earth. What will be Life without this force?
I kept pondering…
Had learnt about Newton’s Laws of Gravitation in School…
Sir Isaac Newton (25 December1642-20 March 1726) was an English Physicist and Mathematician one of the most influential scientist of all times.

g3

What is Gravity?
Gravity is an invisible force that pulls/attracts all matter towards itself. But this force is very very weak that is why the matter does not get pulled with other objects. The fundamental forces of the universe include the electromagnetic, strong nuclear, weak nuclear and gravitational forces. Gravity is the weakest of all but in cases where matter is involved in massive quantities (for example: a black hole), it is the strongest and most dominant one. Gravity is the reason everything gets attracted towards the Earth’s surface, and also for the formation and movement of all the planets and other heavenly bodies.

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(Gravity keeps the moon where it’s supposed to be — in orbit.
Photo courtesy of NASA)
Gravity also is important on a larger scale. It is the Sun’s gravity that keeps the Earth in orbit around the Sun; otherwise Earth would fling drifting in space. Life on Earth needs the Sun’s light and warmth to survive. Gravity helps the Earth to stay just the right distance from the Sun, so it’s not too hot or too cold. It’s the Earth’s gravity that keeps the moon in orbit around the Earth.

inewton
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Isaac Newton discovered Gravitational Force

Newton’s law of universal gravitation, which postulates that the gravitational force of two bodies of mass is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. He also postulated the Law of Motion.

Gravitational Force = G* ___(M1*M2) ______________
(d2)
where ‘G’ is the gravitational constant, ‘m1’ and ‘m2’ are the masses of the two objects, for which the force has to be calculated, and ‘d’ is the distance between the centers of gravity of both masses.

Albert Einstein:gravity-works-3.jpg

In modern physics, gravity is most accurately described by the general theory of relativity (proposed by Einstein) which describes gravity as a consequence of the curvature of spacetime. (Albert Einstein called gravity a distortion in the shape of space-time. Photo by keystone/getty images)

In 1806, a British physiologist called A. Knight demonstrated through an experiment, the control of gravity on the direction of a plant’s root growth. The term geotropism was first coined by A. B. Franck in 1868. It is a growth movement by a plant in response to gravity.

general relativity
If you were to put a plant on its side you would notice that after a while the roots start growing downward while the stem grows upward. This response to gravity is called geotropism, or gravitropism. The roots are exhibiting positive geotropism (growing with gravity) and the stem is exhibiting negative geotropism (growing against gravity).

geotropism
Fun facts about gravity:
Ocean tides are caused by the gravity of the moon.
Mars is smaller and has less mass than Earth. As a result it has less gravity. If you weigh 100 pounds on Earth, you would weigh 38 pounds on Mars. Moon

SOURCE:Buzzle, howstuffworks images from NASA ,Net.

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