can you define buoyancy in simple words for me? why does a ball of clay sink, while a boat shape floats?
2007-10-18 17:49:34 · 5 answers · asked by Sarah S 3 in Science & Mathematics ➔ Physics
GO ASK A LIBRARIAN!
2007-10-18 17:55:37 · answer #1 · answered by ssweeps 3 · 0⤊ 0⤋
The 'force' of buoyancy is equal to the gravitational force exerted on the mass of water that the object displaces. If the object displaces 1 cubic meter of water (1,000 kg) then the buoyant force will be F=ma = 1000*9.8 = 9800 N.
If the mass of the object is less than 1000 kg, it will float because the buoyant force is greater than the force exerted on the objext by the acceleration of gravity. If the objext has a mass of greater than 1000 kg (say, 1500 kg) then it will sink. But, if you suspended it from a scale and lowered it into the water, the scale would measure only 500 kg because the buoyant force is -still- 9800 N.
Doug
2007-10-18 17:59:02 · answer #2 · answered by doug_donaghue 7 · 0⤊ 0⤋
buoyancy is the force an object feels from displacing the fluid around it. it happens b/c in most fluids the pressure is greater as you get deeper or closer to the center of the earth. that means if there's more pressure on the bottom pushing an object up than pressure pushing an object down there is a buoyant force, which is always the case. however, an object also experiences the force of gravity. so if it's weight is more than the force of buoyancy, it sinks. if it's weight is less than the force of gravity, it floats. either way, almost everything, even you and i in air, experience a buoyant force. but b/c we're not helium balloons, we don't float. also the side to side pressures cancel. also to determine if you float in water you just need to know if you're average density is less than that of water. if your density is less than the surrounding medium, your buoyant force will be stronger than your weight, and you will float.
2007-10-18 17:55:50 · answer #3 · answered by keyahnoo 2 · 0⤊ 0⤋
Buoyancy is the force experienced by a solid body immersed in a fluid (fluid means liquid or gas) medium in the upward direction.
One may wonder why there is such an upward force ? When a solid body is inside a fluid, there is less pressure on its upper surface which is in downward direction as compared to the pressure on its lower surface which is in the upward direction. As the force is pressure multiplied by area, there is a greater upward force on it than the downward force due to pressure of fluid which results in a net upwards force. Pressures on left and right hand sides being equal and opposite in direction cancel each other.
It can be proved that the force of buoyancy experienced by the solid body is equal to the weight of the fluid displaced by it.
2007-10-18 18:00:14 · answer #4 · answered by Madhukar 7 · 0⤊ 0⤋
go here: http://en.wikipedia.org/wiki/Buoyancy
2007-10-18 18:00:57 · answer #5 · answered by ~*PrettyInPunk*~ 2 · 0⤊ 0⤋