2007-05-04 05:24:39 · 6 answers · asked by falalu 1 in Science & Mathematics ➔ Physics
buoyancey
2007-05-04 05:28:39 · answer #1 · answered by thepenpal 4 · 0⤊ 0⤋
As one answerer said "buoyancy." Too bad that term wasn't explained. As another answer put it the weight of the body out of water (B) minus the weight of the water displaced by that body (W) when put in the water is less weight felt when in the water. The weight of that displaced water is the buoyancy force acting on the body.
Thus, if B - W > 0 the body's effective weight is that difference, which is a positive number. Thus, the body will sink in the water until it hits bottom. In fact, the body of mass (m) will have a net force f = B - W = ma acting on it; so that a = (B - W)/m is the acceleration of that body as it sinks to the bottom.
But what if B - W = 0? The effective weight or net force on the body is zero; so there is no acceleration downward into the water. And that's what we call floating. The body will float in the water when its effective weight is zero. And the effective weight is zero when the weight of the body out of water exactly equals the weight of the water displaced by that body when in the water.
2007-05-04 12:50:59 · answer #2 · answered by oldprof 7 · 0⤊ 0⤋
The weight of the body = mg
and always acts downwards., towards earth. When the body floats on water or in water, due to the liquid properties of water i.e., Surface tension, Viscosity and density, the body experience upward thrust. The contribution to this force is primarily due to viscosity that arises due to cohesive forces among water particles. This force say F2 acts against the weight of the body. Then
Apparent weight of the body = Actual weight - Upward force (Other wards called buoyancy as in first answer)
= mg - F2.
So that the body weighs less in water.
2007-05-04 12:41:32 · answer #3 · answered by Syama Subbarao Y 1 · 0⤊ 0⤋
Because they do!. while the mass doesn't change, the water helps support the object. The support is = to the mass of water displaced & water has a density of 1kg/liter.
2007-05-04 12:29:52 · answer #4 · answered by yupchagee 7 · 0⤊ 0⤋
The weight of the water above you pushes on all sides of you and thus lifts you up. The difference is your weight minus the weight of the water that you displace.
2007-05-04 12:29:50 · answer #5 · answered by tbolling2 4 · 0⤊ 0⤋
The density of the object or element
2007-05-04 12:31:38 · answer #6 · answered by Anonymous · 0⤊ 0⤋