Game Development Reference
In-Depth Information
A Short Biography of Sir Isaac Newton
Before we delve into the subject of Newtonian mechanics, let's learn a little bit about the man
behind them. Sir Isaac Newton (1642-1727) was an English mathematician, physicist, chemist,
and one of the most brilliant men who ever walked the face of the earth. Newton developed the
basic laws of motion and the law of universal gravitation that are the cornerstones of many
scientific disciplines. In contrast to the breadth of his scientific achievements, he was born into
rather unacademic circumstances. He was born in 1642 the son of a farmer. His father, who died
before Isaac was born, was completely uneducated and was unable to even sign his own name.
Newton attended grammar school as a boy, where his teachers described him as “idle”
and “inattentive.” His mother pulled him out of school at the age of 14 to manage the family
estates, but it quickly became apparent that he had neither the talent nor the inclination to be
a farmer. He was allowed to return to grammar school in 1660. This time he lodged with the
headmaster of the school and began to show some considerable academic promise.
Newton entered university at Trinity College, Cambridge, when he was 18. His original
intention was to pursue a law degree, but during his studies he became interested in the works
on astronomy written by Galileo and Johannes Kepler. His interests broadened into the fields
of mathematics and optics. He gained his degree in 1665, and then had to return home when
Cambridge was closed because of an outbreak of the plague.
When he was at home, still younger than 25 years old, he began a remarkable two-year
stretch where he made revolutionary advances in the fields of mathematics, optics, physics,
and astronomy, including the invention of differential and integral calculus. Newton returned
to Cambridge in 1667, where he continued making a dazzling series of inventions and advance-
ments in multiple academic fields.
Newton's most famous written work is a topic titled
Philosophiae Naturalis Principia
Mathematica
(
The Mathematical Principles of Natural Philosophy
), written in 1687 and considered
one of the most important single works in the history of science. Included in this work were the
descriptions and mathematical formulas that comprised Newton's famous three laws of motion—
subjects that the next three sections of this chapter will briefly describe.
■
Tidbit
Would you like to own a copy of Newton's
Principia
? You'd better start saving your money. A first
edition copy in good condition can fetch upwards of $350,000.
Newton's First Law of Motion: Inertia
The basis of Newton's first law of motion was experimental observations of balls rolling on
inclined and flat planes performed by Galileo. It had been conventional wisdom in Galileo's
time that an external force was required to keep an object moving. Based on his observations,
Galileo concluded that an external force was necessary to change the velocity of an object, but
in the absence of an external force the velocity would remain constant. Newton formalized
Galileo's observations in his
Principia
as his first law of motion:
Every body preserves in its state of rest, or of uniform in a right line, unless it is
compelled to change that state by forces impressed thereon.
