Things are constantly moving: sometimes faster and sometimes slower. The speed depends on two things – the mass and the size of the force.
Isaac Newton discovered this and a number of other things during his lifetime from 1643 to 1727 and was without a doubt one of the most important scientists the world would ever come to know. Newton would closely spy on how things would move and interact. By doing so, he noticed some irregularities. Newton then wrote three laws in 1687. We know them as 'Newton's laws of motion.'
Using these laws, he was the first to explain why things move as they do. Whether it is a particle or a giant truck, these laws make us understand the movement of all things.
There are not many more ideas more fundamental than Newton's three laws of motion in our universe. His laws give people explanations on how a forces relate to each other; why it is so hard to get something moving and then even harder to stop it; and how much force will be needed in starting or stopping someone or something in any given situation. In all its simplicity and beauty, these precepts can be as compelling as a Edgar Allen Poe poem, and like the very best of poetry, these laws identify things that resonate throughout life. The applications of Newton's three laws are endless: from the first breath that a baby takes to the initial seconds of a car crash to the planets continuous movement through the cosmos. The laws of motion are intertwined in our everyday lives more than one thinks, describing physical processes just as much as emotional ones.
The first law states that something in a "slow" position will remain that way, especially when there is no applied force. Imagine a bag that hangs on a cord. The bag remains motionless unless you touch it or there is an outside force, like wind, that moves it. By itself, it will continue to stay still because it does not have the inertia to move itself.
The second law describes what happens when force is applied to something. This happens when the matter is in motion, in a straight line in the direction in which the force acts. For example, if you hit a sack hanging by a rope, you must swing more precisely in the direction in which the sack and rope is hanging or swinging. But not only that: Depending on how much you strike the sack - and how much force you spend – the sack moves faster or slower. So this law depends on the force acting on it. Another important factor to keep in mind is mass of the bag. The greater the mass, the more force you have to spend to put the whole thing in motion.
The third law states that there is always a force to counter an equal force that is acting in the opposite direction. One can easily imagine, if you stand on the floor, the force of gravity will pull you down. There is a balance of forces that keeps you on the spot where you stand. If the soil would not push or pull you with the same force, you would sink into the ground.
When a person thinks of a law, they usually think of injunctions like stealing or assault. These types of human laws are prescriptive and differ from the laws of man and nature. The scientific laws stated by Newton, Galileo and so on, operate exactly the opposite way. The mechanism that ensures nature 'obeys' any laws set forth will always come first. These 'laws' are just descriptive statements concerning evident behavior. With civic and human law, disobeying laws are possible and that is why the justice system exists. However, in scientific law, disobedience is impossible.
Scientific laws do go beyond their limits in some rare cases. Friction prevents an object from behaving accordingly to Newton's first law. Objects on Earth are constantly subject to friction, including everything from liquids to dry bodies. In fact, internal friction or viscosity is always an issue even when air is involved.
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