The force which pulls down is gravity. What about the force which pulls things up?

collect

I am unsure as to what yoiu mean by "pulls things up." If you mean "pushes things apart" (as opposed to gravity which "pulls things together" then there are two forces which you might be referring to to. One is the familiar one of static electricity -- two items which have the same polarity of electric charge will repel each other. Two with opposite polarity will attract each other. And of course magnetic poles -- two "north poles" of par magnets will repel each other, a north pole and south pole will attract each other. If you mean, however, why do we not fall into the earth, the anser is because we hve stuff in the way, and the "in the way" force is exactly equal to gravity, thank goodness. If you are asking why things can float up in the air, the answer lies in Aristotle -- each object in a fluid (air is a "fluid" for this statement) will float in the fluid if it's weight (yes -- all gases have "weight") for the volume of air it displaces is less than the weight of air in the same volume. It will try to reach a point where the two are equal. May 13 07, 6:12 AM

comeplay

the force which pulls things up is known as arche miedies May 13 07, 6:14 AM

collect

Argh!! Did I misstate Aristotle? (sigh) I know I whould wake up sometime! May 13 07, 6:24 AM

MonkeyOnALeash

Centrifugal force will propel things away from an objects center. May 13 07, 8:58 AM

MonkeyOnALeash

Ar·chi·me·des (är'kə-mē'dēz) Greek mathematician, engineer, and physicist. Among the most important intellectual figures of antiquity, he discovered formulas for the area and volume of various geometric figures, applied geometry to hydrostatics and mechanics, devised numerous ingenious mechanisms, such as the Archimedean screw, and discovered the principle of buoyancy.Discovered the principles of specific gravity and of the lever. http://dictionary.reference.com/browse/archimedes May 13 07, 9:01 AM

Baloo55th

There is no force that pulls things up. And as collect says, gravity pulls things together. As we are stood on a rather large lump of stuff, we seem to be pulled down. In fact, we are also pulling the Earth 'up'. The 'force' that things being stood on exert on the things standing on them is called reaction. If I stand on a plank, I exert 130lb of force downwards. The plank exerts 130 lb of reaction force upwards. If the plank can't do this, I go through it. If it exerts more than this, I go upwards (like on a springboard!). May 13 07, 9:07 AM