Did you ever wonder who Sir Isaac Newton was and what he accomplished?

By David McClelland

This is the third in a three-blog series about historical figures. The first two were on Galileo and Leonardo da Vinci.

Sir Isaac Newton lived from 1642 – 1727. He was an English mathematician and physicist. He was one of the foremost scientific intellects of all time. He was born weeks too early and the woman helping with the birth predicted an early death for the weak boy. However, he survived and grew up with his grandmother on the family farm.

Newton was elected a "Fellow" at Trinity College in Cambridge in 1667 and became the "Lucasian Professor of Mathematics" in 1669. He lectured at Cambridge in most years until 1696. Of those years, at which Newton was at the height of his creative powers, he singled out 1665 – 1666 as "the prime of my age for invention." During those two to three years of intense mental effort, he prepared "Philosophic Naturalis Principia Mathematics," commonly known as the Principia, although this was not published until 1687. Newton is credited with inventing calculus. He did experiments with prisms and was the first to determine why the separate colors appear when sunlight passes through a prism. He worked with optics and he was the first to develop a reflecting telescope, which proved to be more powerful than Galileo's refracting telescope, and was quickly accepted.

Newton has been regarded as the founder of modern physical science. His achievements in scientific investigation were as innovative as those in his mathematical research.

There is a popular story that Newton, while observing an apple fall on his head,  suddenly thought of the Universal Law of Gravitation. As in all such legends, this is almost certainly untrue in its details, but the story contains elements of what actually happened. Probably the more correct version of the story is that Newton, upon observing an apple fall from a tree, began to think along the following lines: the apple's velocity was at zero when it was hanging on the tree and, when it fell, it accelerated as it moved toward the ground. Thus, by Newton's 2^nd Law, There must be a force which acts upon the apple to cause this acceleration. Let's call the force "gravity," and the associated acceleration, "the acceleration due to gravity." Then, imagine the apple tree is twice as high and, as the apple falls, it picks up speed in its decent. Newton concluded that the force of an object is equal to its mass times acceleration.

Newton's 1^st Law – An object at rest remains at rest unless acted upon by an outside force. Newton's 3^rd Law – For every action, there is an equal and opposite reaction. 

Newton died on March 27, 1727 and was buried in Westminster Abbey, a great honor. Now, we all know more about Sir Isaac Newton as well.