Hellooo there fellow evolutionary wonders,
In my last post entitled “what exactly is science?” I briefly explained the discovery of the spectrum. 350 years ago, it was discovered that white light is really a mixture of all the different colours. Pretty astonishing considering that white looks quite plain. The spectrum was discovered by a dude called Sir Issac Newton and if you haven’t at least heard of him before then I’m supposing that you were born yesterday.
Sir Isaac Newton (25 December 1642 – 20 March 1727) was an English physicist, mathematician, astronomer, natural philosopher, alchemist, theologian and all round badass. He’s considered by many to be the greatest and most influential scientist who ever lived.
So what’s so great about him?
Well, It turns out that Newton didn’t only discover the spectrum (which is a pretty awesome achievement by its self) he discovered a whole load of things on top of that, forming the basis of the classical age of physics. Arguably, his most famous discovery is that of gravity.
Gravitation, or gravity, is a natural phenomenon by which physical bodies attract with a force proportional to their masses.
There’s a famous incident where he was inspired to formulate his theory of gravitation by watching the fall of an apple from a tree.
While this may or may not be true, the discovery of gravity is a pretty big deal. It meant that scientists could unlock hidden mysteries about the universe. The universal law of gravitation basically states that every object in the universe exerts a tug on every other. It may not seem like it, but as you sit here now you are pulling everything around you-walls, the ceiling, phones, people-towards you with your own very little gravitational field. What’s more, these things are pulling on you.
The heavier the object i.e the more mass it has, the more things it attracts so the larger its gravitational field.
Gravity was so important because amongst other things, it explains the elliptical orbits of planets and comets suchlike, as well as the attractive force that got them moving in the first place.
Newton’s formula was the first real universal law of nature. Suddenly every motion in the universe made sense-the slosh and roll of ocean tides, the motions of planets, why cannonballs trace an arc before thudding back to Earth and why we aren’t flung into space as the planet spins beneath us at hundreds of miles an hour. Think about it, without gravity we wouldn’t even be here and Newton was the first person to acknowledge this principle.
And that’s not all.
At the heart of Newton’s theories were the three laws of motion:
1) The first law states that object at rest tends to stay at rest, and an object in motion tends to stay in motion, with the same direction and speed. Motion (or lack of motion) cannot change without an unbalanced force acting. If nothing is happening to you, and nothing does happen, you will never go anywhere. If you’re going in a specific direction, unless something happens to you, you will always go in that direction. Forever.
2) Everyone unconsciously knows the Second Law. Everyone knows that heavier objects require more force to move the same distance as lighter objects. For example, it takes more work to throw a washing machine across a room than a tennis ball. The second law shows that if you exert the same force on two objects of different mass, you will get different accelerations (changes in motion). The effect (acceleration) on the smaller mass will be greater (more noticeable). The effect of a 10 newton force on a tennis ball would be much greater than that same force acting on a truck. The difference in effect (acceleration) is entirely due to the difference in their masses.
Here’s a simple mathematical problem:
Using the formula F=MA, you can figure out that if the force of the drag by the wolf is a 100N and the mass of the giant rock on the sledge is 50 kg, then by dividing F by M you can get A (the acceleration). In this case it’s 2 m/s2
Because, the standard unit of acceleration is meters per second squared
3) The third and final law is the most well known. The third law says that for every action (force) there is an equal and opposite reaction (force). Forces are found in pairs. Think about the time you sit in a chair. Your body exerts a force downward and that chair needs to exert an equal force upward or the chair will collapse. It’s an issue of symmetry. That example is similar to the kick when a gun fires a bullet forward. When the bullet is fired the same amount of force applies to the gun but if you remember the previous law you’ll know that it it’s less noticable on the gun, which is why it just jerks back instead of flying across.
So, Newton’s theories made him instantly famous. Newton produced all his findings in the three-volume Philosophiae Naturalis Principia Mathematica. Although it has been called ‘one of the most inaccessible books ever written’, the principia was a beacon to those who could follow it. What’s more, Newton published this book on a basis of a bet. Just to win it, Newton invented the whole system of calculus, which is mind-blowingly impressive because most of us have difficulties even trying to comprehend it.
As usual, I’ve only provided a brief summary of his discoveries, achievements and life. There’s much more to this brilliant man. But what I find even more astonishing is that Newton single-handedly grasped the mysteries of the cosmos. He wasn’t the kind of person to say “I don’t know” to an answer, he would devise new methods or mathematics to answer questions that people wouldn’t even think of asking. He was way ahead of his time.
All this by the age of 26. Pretty impressive huh?