Tuesday, 19 July 2016
Earth has a gravity field like a teen ... all on its own terms!!
Of the terrestrial planets in the solar system, Earth is not only the largest body but also the most massive. A calculation of its weight puts it slightly over 6.58 sextillion tons (that's 6.58x10^21 or 6,580,000,000,000,000,000,000). It's heavy because everything on our planet has mass—from the land that covers the continents to the water that fills the oceans. Earth's mass, however, isn't distributed evenly.
Gravity is often assumed to be the same everywhere on Earth, but it varies because the planet is not perfectly spherical or uniformly dense. In addition, gravity is weaker at the equator due to centrifugal forces produced by the planet’s rotation. It’s also weaker at higher altitudes, further from Earth’s centre, such as at the summit of Mount Everest.
These differences mean that in the unlikely event that you found yourself falling from a height of 100 metres, you would hit the surface in Peru about 16 milliseconds later than in the Arctic. You would also lose 1 per cent of your body weight in moving from the Arctic to the Peruvian mountaintop, although your mass would not change
RANDOM FACT !!
To leave Earth’s gravitational pull behind, an object must travel 7 miles a second, our planet’s escape velocity.
Gravity is by far the weakest of the four fundamental forces. The other three are electromagnetism; weak nuclear force, which governs how atoms decay; and strong nuclear force, which holds atomic nuclei together.
Einstein’s general theory of relativity was the first to treat gravity as a distortion of space-time, the “fabric” that physically embodies the universe.
ufo sighting over Cape Town,South Africa