Make all capitalization consistent with the rules of convention outlined in the American Heritage Dictionary. DO capitalize: The first word and any proper nouns in a title, heading, or subheading. Proper nouns, months, days of the week, but not the seasons.
Newton (unit) The newton (symbol: N) is the SI unit of force. It is named after Sir Isaac Newton because of his work on classical mechanics. A newton is how much force is required to make a mass of one kilogram go faster at a rate of one metre per second squared.
Isaac Newton (a 17th century scientist) put forth a variety of laws that explain why objects move (or don't move) as they do. These three laws have become known as Newton's three laws of motion. The focus of Lesson 1 is Newton's first law of motion - sometimes referred to as the law of inertia. Newton's first law of motion is often stated as An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.