Thursday, 4 February 2016

32 “If “gravity” is credited with being a force strong enough to hold the world’s oceans, buildings, people and atmosphere stuck to the surface of a rapidly spinning ball, then it is impossible for “gravity” to also simultaneously be weak enough to allow little birds, bugs, and planes to take-off and travel freely unabated in any direction.”

If gravity is strong enough to hold everything on the earth, how can birds and bugs overcome it? 

Because gravity is very weak, by far the weakest of the forces. A small fridge magnet can lift a pile of nails against the gravitational pull of the whole earth.  But gravity doesn’t have to be very strong to hold us, and the oceans, on to the surface. There’s only a much tinier effect, the centrifugal force of the rotation, that it has to overcome. No other force or effect is pulling us away form the ground.

But Dubay’s  words and especially his  picture of upside down Australia seem to suggest you think that gravity has to stop the oceans falling off the “bottom” of the world into space? Of course not. 

Remember, “down” is towards the centre of the earth, not towards outer space in the direction of the south pole.

 What would pull the ocean’s waters away from the Earth? There’s only so-called centrifugal force, which is actually the inertia of the water “trying” to keep  moving in a straight line at a tangent to the Earth, It’s easy to calculate that this is much weaker still than gravity.

So gravity doesn’t have to be enormously strong to hold all the loose stuff on the earth. There’s nothing strong enough pulling it off.

No comments:

Post a Comment

(Please make your comment reasoned and based on evidence . Abusive comments will be totally ignored.)