Apr 07, 2022
In Classroom Management
If the gravity of the Earth were to be turned off, the Earth would leave its circular trajectory and travel straight with a high velocity, reaching 50 billion Telephone Number List miles out from the Sun in a century's time. Hence, it is the Telephone Number List gravitational forces of both the Sun and the Earth, that holds the Earth in a orbit around the Sun. The orbiting Earth may be compared to a piece of stone tied to a string, which is swung in a circle holding the string at one end. If you were to let go of the string, the stone, tied at the other end of Telephone Number List the string, will fly off at a straight trajectory, just as Earth would do, if the gravity were to be turned off. This force is termed as the 'Centrifugal force.' There can be a question about the time required to complete one orbit. Does that depend upon the distance at which the Telephone Number List object is orbiting? After years of experiments, it was found out, that the greater the distance, the more time it takes to complete one orbit. This was deduced from the formula, that the time taken, is directly Telephone Number List proportional to the distance of the object around which it is orbiting. Thus, the planet which is at a larger distance from the Sun, takes longer to complete one orbit. This time Telephone Number List taken to complete one orbit is termed as 'orbital period.' Looking at the first law of Newton, it was understood that in principle it should be possible to put up a man-made satellite in the sky, which Telephone Number List would orbit the Earth. As has been seen, this satellite would need a sideways velocity, like the earth, so that it does not fall back on Earth. If such a satellite is put up in the sky at a distance of 4,000 miles, it will have a Telephone Number List orbital period of approximately 90 minutes. To miss falling on to the Earth, this satellite would have to have a sideways Telephone Number List velocity of 17,000 miles per hour.