When was inertia discovered

In truth, gravity was discovered by a gentleman by the name of Ug , who lived in a cave in northern Europe approximately 30, years ago. Common legend also has it that Galileo proved that gravity pulls on all objects equally. He proved this by dropping two objects of the same size but different weights, such as a lead ball and a wooden ball.

Most historical records indicate that Galileo himself probably never performed this experiment, although he discussed the ideas. Of course, actually performing this experiment with accuracy in the year would have been difficult due to air resistance and the technology of the times.

Simon Stevinus is reported to have actually performed this experiment among others. In modern times, to eliminate air resistance, David Scott performed this experiment during the Apollo 15 mission to the moon. Another great myth is that Galileo invented the Scientific Method. The Scientific Method is taught widely in science classroom and is often used from local science fairs to NASA educational demonstration.

The idea of the Scientific Method is that a student develops a hypothesis, designs an experiment, gathers data, analyzes the data and make conclusions. In fact, it should be noted that the National Academy of Science in their Next Generation Science Standards clearly states that there is not one method for doing science.

Scientists use a combination of planned experimentation, modeling, trial and error, and pure exploratory research. There is a nice article of further reading in Student Science for which I was interviewed. To emphasize this myth I quote Harmon Craig, the winner of Balzan prize equivalent of Nobel in natural science. Well, the scientific method is what you learned in My Weekly Reader when you were in grammar school, but no first-rate scientist uses it.

So where did this idea come from? The Scientific Method was developed in by Karl Popper. Another interesting myth is that Galileo invented experimentation. Again, he was beaten to the punch by Ug the Caveman, who invented the wheel. Galileo did promote the use of experimentation, and popularized the used of experimentation in developing arguments. If a ball rolls down a hill, when it reaches the level part of the hill, eventually the ball will come to a stop.

In his great text, Physica, Aristotle provides an explanation of motion. Objects have a natural place which they seek. For instance, objects made of wood, rock, and metal tend to seek out the Earth as that is their natural place to be.

Objects made from air seek out the heavens and will tend to rise. This is natural motion. Violent motion would be something we do against an objects nature. So an exerted force will cause an object to move. Thus consider a ball rolling across the ground. Newton expanded upon the earlier work of Galileo Galilei , who developed the first accurate laws of motion for masses, according to Greg Bothun, a physics professor at the University of Oregon.

Galileo's experiments showed that all bodies accelerate at the same rate regardless of size or mass. Newton also critiqued and expanded on the work of Rene Descartes, who also published a set of laws of nature in , two years after Newton was born. Descartes' laws are very similar to Newton's first law of motion. Back then, most people believed that the natural state of a body was to be at rest. It was obvious that imparting motion to a body at rest required the application of an outside force.

However, it was also believed that it required a continuous outside force to keep a body in motion. Based on their experience with everyday objects, this was not an entirely unreasonable conclusion. After all, if your horse stopped pulling, your wagon would stop rolling, and if the wind stopped blowing, your boat would stop moving.

People therefore assumed that these objects were simply reverting to their natural rest state. It took a remarkable leap of intuition to realize that there had to be an outside force acting to stop the motions of these objects. Take the case of a flat stone sliding on the smooth surface of a frozen lake.

He discovered that light rays travel the same both backwards and forwards. He invented functions of variables and their "courses" what we'd call "first derivatives" in modern calculus. He discovered the law of inertia, that bodies in motion remain in motion unless something impedes their movement , literally a thousand years before Galileo, Newton, et al.! See the discussion into his Dialogo , page of Th. Salusbury 's English translation :. Now tell me, what would befall the same moveable upon a superficies that had neither acclivity nor declivity?

Well: but if there be no cause of retardation, much less ought there to be any cause of rest. How long therefore would you have the moveable to move? Therefore if such a space were interminate, the motion upon the same would likewise have no termination, that is, would be perpetual. That hath been already supposed, when it was said, that all external and accidental impediments were removed, and the brittlenesse of the moveable in this our case, is one of those impediments accidental.

Tell me now, what do you think is the cause that that same Ball moveth spontaneously upon the inclining plane, and not without violence upon the erected?

But is there any such superficies in the World? Then a ship which moveth in a calm at Sea, is one of those moveables, which run along one of those superficies that are neither declining nor ascending, and therefore disposed, in case all obstacles external and accidental were removed, to move with the impulse once imparted incessantly and uniformly.

The newtonian formulation is basically due to Descartes' Principia philosophiae , art. Altera lex naturae : quod omnis motus ex se ipso sit rectus; et ideo quae circulariter mouentur, tendere semper ut recedant a centro circuli quem describunt. I don't have any references, but I recall reading that he used inclined planes and marbles. Since the speed of a rolling marble is far less than a free falling one, air drag is much less noticeable.

He then realized that if you let a marble go down a slope it will gain velocity, and if then it is forced to go up another slope, ir will stop at exactly the same height where it started, no matter the angles of the slopes.

A similar experiment can be made with a pendulum: no matter if you bend the thead, the top height of the pendulum at both sides of the oscillation is always the same. Then Galileo reasoned: if the angle of the second up slide is very small, the distance needed to reach the original height will be very large. And if the angle is exactly 0, then the distance will be infinite and the marble will roll forever! The failure in Galileo theory is that it only worked horizontally.

You have to wait until Newton to get a really general law of conservation of movement. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group.