In this case, the car is the external force that acts upon the giraffe. When the wall stops the car, the giraffe continues to move. You’ll notice that the giraffe is also in motion. When the car hits the wall, it changes state and stops moving. That’s where the wall comes in- that’s an external force.

According to Newton’s first law of motion, the moving car should continue to move…unless something else causes it to stop moving. Here we see a giraffe traveling along in a tiny car. The following gif best explains Newton’s first law:

The opposite is also true- when an object is stationary, it will remain that way until something causes it to move. You may have learned it as the following: “Every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force” When an object moves, that movement will continue until something else causes it to stop. “Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.”Īs any inspiring physics tutor would explain, this is also known as Newton’s law of inertia. These three laws are a crucial part of physics, and we’ve provided three simple examples to help you in your understanding of Isaac Newton and his Three Laws of Motion! In Principia, Newton outlines his laws of motion and universal gravitation- laws that describe movement as a direct result of the surrounding environment. Sir Isaac Newton, English author, mathematician, theologian, astronomer, and physicist, wrote his Philosophiæ Naturalis Principia Mathematica, a book that changed the way scientists thought about mechanics and the way we interact with the physical universe. Understanding Isaac Newton and his Three Laws of Motion

Sir isaac newton laws of motion