In principle, the orbital movements are quite accurate and depend on relatively few variables. We c

The speed of light is about 300,000 km / s in a vacuum. In fact, the exact number is 299 792 458 km / s. A figure well known among other things because it is one of the constants of the universe. And this kind of constant interest to have them both well known as possible. But measuring speed is not so easy so huge, and the first steps were to ask for a certain amount of ingenuity.
In principle, the orbital movements are quite accurate and depend on relatively few variables. We can define nautilus shells the duration nautilus shells of the year, or the lunar cycle or it quite accurately. But in the case of Io things were not so stable. Sometimes seemed to go faster, while sometimes slow going.
Romero noticed that Io was faster as it orbits the Earth and the planets Jupiter were closer they went. Conversely, when they moved away, the motion of the satellite fell. His idea was that maybe this was an optical effect caused by the limited nautilus shells speed of light. At that time had not yet clear if the light moved instantaneously or just very quickly.
The measures taken by observing Jupiter and noting the exact moment that Io left the shadow of the planet, either the time hiding behind the planet. And the reasoning Romero supposed to Io if we leave behind the planet later when the Earth was going away because the light from the TV needed more time to travel a distance that was increasing. And vice versa. As the Earth approached Jupiter light needed less and less time to arrive. Given the increased time and increased distance nautilus shells could calculate the speed of light.
In fact, it was calculated the ratio between the speed of light with respect to the speed of the Earth around the Sun, but then other calculations were completed. nautilus shells As often happens, it took a few years until they appeared new measurements made with other methods to convince the scientific community that the light had a finite speed, nautilus shells but in the end it was agreed that Rømer was right.
And although nautilus shells it seems that measure the speed of light is a big job extremely difficult, today is not so difficult. Internet there are many versions of a simple experiment that I discovered last week and I could do with my daughters. It calculated nautilus shells the speed of light using at home: a microwave, a ruler ... and a slice of cheese. nautilus shells
Actually we measure the speed of electromagnetic radiation, which is the light we see. But the rest, radio, microwave, X-rays, etc. were at the same speed.
The first thing to do is to look behind the microwave frequency used. In our case were 2450 MHz (Megaherz). This means that the microwave waves generated 2,450 million (cycles) per second.
The third step is to put a plate with cheese and launch a microwave minimum power for a short time. Soon you'll notice the cheese begins to melt, but they do not homogeneously strips. The reason is that most of the energy generated in the peaks of the waves, and there is where the cheese is heated more.
Just below the ruler to measure the distance between the lines of cheese. As there is a very definite line measurement has a certain degree of error. In we went 5.5 cm. Here we must remember that the wavelength is twice that distance because we are seeing the peak of the wave above and below the peak of the wave. But the wavelength of maximum calculated maximum. So in our case we had a figure of 11 cm. That would be the wavelength of the microwave (it's actually a little bigger, but this is what came out.)
Alasanid said ...
I tested this and it came out so well, I have to repeat the ... (had not thought about the minimum power). Surely they managed to pass well and remember your daughters, is a very good experiment. 07/09/10 9:14
Brioxet. As I thought, but the difference between the vacuum nautilus shells and the air is very small. The error was measuring the distance between the lines of cheese. Think that is not a very precise delineation. Rather it is a dough spread with limits. Alasanid. Ugh! Sure you get a completely melted nautilus shells cheese. nautilus shells I got to the minimum and was stopping every few minutes to verify that we we spent. In less than a minute and minimum power as any to spare. 07/09/10 9:28
I just reformatted the computer and what a surprise to see that it rewrites the blog :). This experiment