A question on earth and gravity (theoretically speaking)?
374485
you wont stop "falling" once you got to the ceter of the earth, but by that time you would have a bunch of speed. gravity woulnd't overcome this speed until you got almost all the way to the other side of earth - the whole way assuming earth is a perfect sphere and there is no air resistance. you would basically be a pendulum going back and forth - a pendulum or a swing stops falling in the middle but keeps going because it still has speed. air resitance would eventually slow you down until you want shorter and shorter distances and wound up in the center of the earth, then you would have to climb out. if you were smart, you would grab onto the wall the first time you reached the other side, and climb out only a short distance.\n\nalso the first guy is wrong and the 4th one is right, gravity decreases when you go into the earth - it is strongest right on the surface.
1081992
What you are saying is possible, yet the weight or gas would have to be escaping from earths atmospere or else the mass is still there.  It is a very intetresting idea, though.  \n\n If the weight of the earth dropped then the distance between the earth and sun would increase since the mass is directly proportional to the force between them.
509642
Earth isn't in a strong enough gravitational pull of another planet. There is no "up" or "down" in space. Earth is constantly moving, the solar system moves, the galaxy moves. \n\nI have a question for you...\nHow would you define which direction we would fall in space? Gravity is the reason we fall on Earth.
331061
'Weight' is actually the wrong term since it describes 'mass multiplied by the force of gravity', what you are probably referring to is the 'mass' of earth.\n\nThe earth is not an entirely closed system, so its mass would have changed over history, if only in insignificant quantities. Such as space shuttles leaving, meteors hitting earth and other such external influences.\n\nDestruction of earth such as nuclear explosion would NOT result in any change in mass though, merely a change in state.
1091336
Things would weigh less than on earth\n\nst
79989
Still more theory than fact.\nIt is responsible for the force of gravity.
61784
That's an interesting qts. I assume that you wish to invlove pure physics in this qts. Forget all the heat at the core of the earth and also air resistance.\nConsider pure gravitation theory.\n\nIf say the fellow who fell in the hole has mass m\n\nThen force of gravity exerted by the earth is :\n\n  F = GMm/(r*r) ..... Where G - universal gravitation constant\n\n                            M - Mass of the earth\n                            r - distance between earth and body of mass m\n\n          acceleration due to gravity\n            = (1-h/R)g   .... where h is distance of body beneath the earth's surface and g is acceleration due to gravity at the surface of the earth.\n\nSo as the body comes closer to the core of the earth, h tends to R.\nSo the acceleration of the body goes on decreasing very much. So, body may not actually hover, since his velocity will be constant the instant it is at the core.
141031
because the earth is causing the gravity... everything in space has gravity. How much gravity depends on the objects mass. Bigger mass bigger gavitational pull.
1172003
No.  In fact, gravity is not even the same everywhere on earth now, because earth is not a perfect sphere of uniform density.  Local variations in the earth's mass and topography produce local differences in gravity (so you might expect to weigh slightly differently atop Mount Whitney than you would at the bottom of Death Valley).  Also, the earth's gravitational field has not been constant over time due to changes and redistributions of the earth's mass and shape.  The polar ice caps have pushed down the earth beneath them, flattening the poles compared with a perfect sphere.  Even the tides alter the earth's shape and mass distribution on a daily basis.  To the extent that the earth has accumulated meteorites and particles from space, its total mass has also changed over time.  Since gravity is the attraction between two masses and a function of their relative distances, things which change the masses and their respective distances will result in corresponding changes in the measurement of gravity.
25445
The earth is APPROXIMATELY round due to gravitational forces.
993361
Hrmm the problem is "path relative to what frame of reference"?  See, the earth is moving along in a straight line through the curved or warped space of the Sun's gravity well.  But, I guess you're looking for the answer:  straight line.
110744
Short answer: usam da inverse square law Jar Jar!\n\nLong answer:\n\nNewton simplified things by picturing all of a planets mass gathered in a single point in the center of the planet and the surface as a point on a certain distance from that center of mass. So the gravitationall pull (F) on a body (m) at a distance (r) from the mass (M) can be calculated using this equation:\n\nF=G*((M*m)/r^2)\n\nwhere G is the gravitational constant (6.67 * 10^-11 Nm^2kg^-2)\nEarths (equatorial) radius is 6.378 * 10^6 meters and its mass is\n5.974 * 10^24 kilogrammes\nSo lets test this on a dude weighing 100 kg:\n\n6.668 * 10^-11*((5.974*10^24 * 100)/4.068*10^13)\n==>\n6.668 * 10^-11*(5.974*10^26 /4.068*10^13)\n==>\n6.67 * 10^-11* 1.424*10^13 \n=\n979 N (what I got in my calculator)\n\nSo earth pulls on a guy, with the mass 100 kg, with the force of 979 Newtons. That means 9.79 N/kg, earths gravitational force (g). This should also mean that a mass dropped from a small height should accelerate at the rate of 9.79 m/s^2. It´s a simple experiment to do but where I am the value of g is actually 9.82. This is because I am closer to the earths center. Earth bulges out at the equator because of its rotation. I am farther north. But still a simple experiment can be done to validate this calculation. \nSo if the earths mass was 3 times greater than g shoud be 3 times greater. Right? You betcha. And I have already shown that moving closer to earths center increases g. Moving twice as far from the center should decrease g by half. Right? Wrong! Now what? We where so close. Oh man...\ng is reduced to a quarter if we increase the radius by 2. This is because of the inverse square law, a very important law in astronomy. It means that the apparent brightness of a light source is inversely proportional to the square of its distance. This also aplies to gravitational fields. Double the distance, divide by 4.\nSo lets put this all together. You should be able to do it yourself by now. I got 734 N or 75 % of the dudes weight on earth. And the reason he doesn´t weigh more than on earth is because of the inverse square law. Eventhough the new world is three times as massive we still moved twice as far away from the center. So take the weight of your astronaut, multiply by 3 and divide by 4.
264989
You need to be more specific.\n\nWhat exactly do you mean by "Size"? Do you mean if Earth has the same mass as Jupiter, the same Volume as Jupiter, Both?\n\nIf Earth had the mass of Jupiter but the same volume as it has today, gravity would be much stronger.  The force of gravity is largely dependent on the distance away from the center of mass, thus we would be much closer to a larger center of mass.....we would weight A LOT more.\n\nIf Earth has the same mass as it does today, but had the volume of Jupiter gravity would seem to be a lot weaker.  We would be farther away from the Earth's center of mass and gravity would have a weaker effect on us, we would be much lighter.\n\nIf Earth has the same volume and mass as Jupiter, we would weigh more since the increase in volume is more than canceled out by the (excuse the term) massive increase in mass.
1093836
Centrifugal force and gravity.
770211
each and every material is pulled towards the centre of the earth due to gravitational force.  since the object itself is placed at a depth equal to the radius of the earth, which means it is placed at the centre of the earth, it would not be pulled towards any point and hence the gravity at that point is zero.  when gravity is zero, naturally the weight is also zero.  but remember, there won't be any change in the mass of the body.
436928
If the Earth's radius were bigger, and the mass of it stayed the same, then you would weigh lighter.  That's because with a bigger radius, you're farther away from the centre of gravity, therefore less pull.  If the mass change, then the situation would be different.
821321
All the mass on the earth is being pulled in by gravity, you and me included. the more mass you have the more an object pulls towards itself and others (basically heavy things have a sort of pull, so when you are by a huge mountain you are actually being pulled towards it) \n\nThe easiest way of all the mass to be pulled together is in a sphere, there are no corners and its cannot be compressed without other areas moving further away from the centre, so theoreticlaly the earth SHOULD be a sphere\n\nBUT it isn't; due to its rotation it is fatter than it is tall, because of mass being moved out by centrifugal force. \n\nhope this helps