When was velocity discovered

Galileo may well best be remembered for his battle with the Catholic Church over his support for Copernicus' heliocentric model of the solar system, but perhaps he deserves to be remembered as the founder of modern physics. As early as , Galileo discovered that falling bodies are uniformly accelerated. He then worked out a number of mathematical consequences of this fact, some of which could be confirmed by experiment.

His work was held back by primitive equipment — for example, there were no stop watches available. Part of his work concerned projectiles, and he was aware that their paths are parabolic. Next page - History and applications - Sir Isaac Newton — Doubling one's speed would also mean halving the time required to travel a given distance. If you know a little about mathematics, these statements are meaningful and useful.

The symbol v is used for speed because of the association between speed and velocity, which will be discussed shortly. Don't like symbols? Well then, here's another way to define speed.

Speed is the rate of change of distance with time. In order to calculate the speed of an object we must know how far it's gone and how long it took to get there. Let's say you drove a car from New York to Boston. The distance by road is roughly km miles. If the trip takes four hours, what was your speed?

Applying the formula above gives…. This is the answer the equation gives us, but how right is it? Was 75 kph the speed of the car? Yes, of course it was… Well, maybe, I guess… No, it couldn't have been the speed. Unless you live in a world where cars have some kind of exceptional cruise control and traffic flows in some ideal manner, your speed during this hypothetical journey must certainly have varied.

Thus, the number calculated above is not the speed of the car, it's the average speed for the entire journey. In order to emphasize this point, the equation is sometimes modified as follows…. Read it as "vee bar is delta ess over delta tee". This is the quantity we calculated for our hypothetical trip.

He said that a force which moves a mass a distance D in time T will move half the mass twice the distance in the same time. While the result of his equation is not correct where the force is gravity he was concerned with preserving proportionality , it and his other rules of motion indicate that he employed the concept of average speed. The exact notion of speed, and its precise definition are due to Galileo. But long time before him people had a good intuitive concept of speed, and could use it.

The notions of momentary speed and average speed were confused, of course. One example where the notion of speed was used before Galileo is "dead reckoning" in navigation, which is the computation of the place of the ship using time traveled, speed and direction. Columbus who lived roughly a century before Galileo was a great master of this art, one of his extraordinary achievements was steering his fleet in the second transatlantic voyage exactly to the place where he left a party in his first voyage.

So he had a very clear concept of speed, though the means of measuring it were very primitive. He also tried to use astronomy in his navigation but without great success.

The Italian physicist Galileo Galilei is credited with being the first to measure speed by considering the distance covered and the time it takes. Galileo defined speed as the distance covered per unit of time. 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. Create a free Team What is Teams? Learn more. When and by whom was the earliest definition of speed given?

Ask Question. Asked 6 years, 6 months ago.