Top 10 Scientific Laws and Theories that you Should Really Know.

 10. Big Bang Theory If you're going to know one scientific theory, make it the one that explains how the universe arrived at its present state. Based on research performed by Edwin Hubble, Georges Lemaitre and Albert Einstein, among others, the big bang theory postulates that the universe began almost 14 billion years ago with a massive expansion event. At the time, the universe was confined to a single point, encompassing all of the universe's matter. That original movement continues today, as the universe keeps expanding outward. The theory of the big bang gained widespread support in the scientific community after Arno Penzias and Robert Wilson discovered cosmic microwave background radiation in 1965. Using radio telescopes, the two astronomers detected cosmic noise, or static, that didn't dissipate over time. Collaborating with Princeton researcher Robert Dicke, the pair confirmed Dicke's hypothesis that the original big bang left behind low-level radiation detectable throughout the universe.

9.Hubble's Law of Cosmic Expansion:
 Let's stick with Edwin Hubble for a second. While the 1920s roared past and the Great Depression limped by, Hubble was performing groundbreaking astronomical research. Hubble not only proved that there were other galaxies besides the Milky Way, he also discovered that these galaxies were zipping away from our own, a motion he called recession. In order to quantify the velocity of this galactic movement, Hubble proposed Hubble's Law of Cosmic Expansion, aka Hubble's law, an equation that states: velocity = H0 × distance. Velocity represents the galaxy's recessional velocity; H0 is the Hubble constant, or parameter that indicates the rate at which the universe is expanding; and distance is the galaxy's distance from the one with which it's being compare.

8.Kepler's Laws of Planetary Motion:
Kepler's three laws of planetary motion -- formed in the early 17th century -- describe how planets orbit the sun. The first law, sometimes called the law of orbits, states that planets orbit the sun elliptically. The second law, the law of areas, states that a line connecting a planet to the sun covers an equal area over equal periods of time. In other words, if you're measuring the area created by drawing a line from the Earth to the sun and tracking the Earth's movement over 30 days, the area will be the same no matter where the Earth is in its orbit when measurements begin.

7.Universal Law of Gravitation:
 We may take it for granted now, but more than 300 years ago Sir Isaac Newton proposed a revolutionary idea: that any two objects, no matter their mass, exert gravitational force toward one another. This law is represented by an equation that many high schoolers encounter in physics class. It goes as follows: F = G × [(m1m2)/r²] F is the gravitational force between the two objects, measured in Newtons. M1 and m2 are the masses of the two objects, while r is the distance between them. G is the gravitational constant, a number currently calculated to be 6.672 × 10-11 N m² kg-2 The benefit of the universal law ofgravitation is that it allows us to calculate the gravitational pull between any two objects. This ability is especially useful when scientists are, say, planning to put a satellite in orbit or charting the course of the moon.

6.Newton's Laws of Motion:
 The first of the three laws states an object in motion stays in motion unless acted upon by an outside force. For a ball rolling across the floor, that outside force could be the friction between the ball and the floor, or it could be the toddler that kicks the ball in another direction. The second law establishes a connection between an object's mass (m) and its acceleration (a), in the form of the equation F = m × a. F represents force, measured in Newtons. It's also a vector, meaning it has a directional component. Owing to its acceleration, that ball rolling across the floor has a particular vector, a direction in which it's traveling, and it's accounted for in calculating its force. The third law is rather pithy and should be familiar to you: For every action there is an equal and opposite reaction. That is, for every force applied to an object or surface, that object pushes back with equal force.

5 .Laws of Thermodynamics The British physicist and novelist C.P. Snow once said that a non scientist who didn't know the second law of thermodynamics was like a scientist who had never read Shakespeare].His now's now- famous statement was meant to emphasize both the importance of thermodynamics and the necessity for non scientists to learn about it. Thermodynamics is the study of how energy works in a system, whether it's an engine or the Earth's core. It can be reduced to several basic laws, which Snow cleverly summed up as follows You can't win. You can't break even. You can't quit the game. Let's unpack these a bit.

By saying you can't win, Snow meant that since matter and energy are conserved, you can't get one without giving up some of the other (i.e., E=mc²). It also means that for an engine to produce work, you have to supply heat, although in anything other than a perfectly closed system, some heat is inevitably lost to the outside world, which then leads to the second law.
 The second statement -- you can't break even -- means that due to ever- increasing entropy, you can't return to the same energy state. Energy concentrated in one place will always flow to places of lower concentration.
Finally, the third law -- you can't quit the game -- refers to absolute zero, the lowest theoretical temperature possible, measured at zero Kelvin or (minus 273.15 degrees Celsius and minus 459.67 degrees Fahrenheit). When a system reaches absolute zero, molecules stop all movement, meaning that there is no kinetic energy, and entropy reaches its lowest possible value. But in the real world, even in the recesses of space, reaching absolutely zero is impossible -- you can only get very close to it.

 4.Archimedes' Buoyancy Principle :
According to Archimedes'buoyancy principle, the force acting on, or buoying, a submerged or partially submerged object equals the weight of the liquid that the object displaces. This sort of principle has an immense range of applications and is essential to calculations of density, as well as designing submarines and other oceangoing vessels.

 3. Evolution and Natural Selection In a basic sense, this differentiation occurred through evolution, through descent with modification

 Populations of organisms developed different traits, through mechanisms such as mutation. Those with traits that were more beneficial to survival such as, a frog whose brown coloring allows it to be camouflaged in a swamp, were naturally selected for survival; hence the term natural selection. It's possible to expand upon both of these theories at greater length, but this is the basic, and groundbreaking, discovery that Darwin made in the 19th century: that evolution through natural selection accounts for the tremendous diversity of life on Earth.

2.Theory of General Relativity:
Albert Einstein's theory of general relativity remains an important and essential discovery because it permanently altered how we look at the universe. Einstein's major breakthrough was to say that space and time are not absolutes and that gravity is not simply a force applied to an object or mass. Rather, the gravity associated with any mass curves the very space and time (often called space-time) around it.

 To conceptualize this, imagine you're traveling across the Earth in a straight line, heading east, starting somewhere in the Northern Hemisphere. After a while, if someone were to pinpoint your position on a map, you'd actually be both east and far south of your original position. That's because the Earth is curved. To travel directly east, you'd have to take into account the shape of the Earth and angle yourself slightly north. (Think about the difference between a flat paper map and a spherical globe.)

1. Heisenberg's Uncertainty Principle :
Einstein's broader theory of relativity told us more about how the universe works and helped to lay the foundation for quantum physics, but it also introduced more confusion into theoretical science. In 1927, this sense that the universe's laws were, in some contexts, flexible, led to a groundbreaking discovery by the German scientist Werner Heisenberg. In postulating his Uncertainty Principle, Heisenberg realized that it was impossible to simultaneously know, with a high level of precision, two properties of a particle. In other words, you can know the position of an electron with a high degree of certainty, but not its momentum and vice versa. Niels Bohr later made a discovery that helps to explain Heisenberg's principle. Bohr found that an electron has the qualities of both a particle and a wave, a concept known as wave- particle duality, which has become a cornerstone of quantum physics. So when we measure an electron's position, we are treating it as a particle at a specific point in space, with an uncertain wavelength. When we measure its momentum, we are treating it as a wave, meaning we can know the amplitude of its wavelength but not its location.