The weight of the substances are largely immaterial. What matters is the density. Assuming fresh water to have a density of 1.0 anything with a lighter density will float in it. For example, oil generally has a density of about 0.8, so it floats in water. Concrete has a density of about 2.4, so it sinks.
http://physics.about.com/od/fluidmechanics/a/commondens.htm
An object that floats has a density (or specific gravity) slightly less than the liquid it floats in. The weight of the fluid it displaces is the same as the weight of the volume of the object below the surface of the liquid.
The upward buoyant force is simply equivalent to the weight of an amount of the fluid that would occupy the same space (same volume). The total upward force on the body, if freely floating, would be found by subtracting the downward force of the body's own weight. So for example, the buoyant force on a balloon filled with air submerged in water would be equal to the weight of the same-size balloon filled with water suspended in air.
The weight is due to the force exerted on the body by the gravitational pull by the earth. If no such gravitational pull on the body, then the body becomes weightless. In free space, very far away from the earth the astronauts experience weightlessness. So if M is the mass of the body, then Mg is the weight of the body. Hence weight depends on the value of 'g'. The value of g is the least at the equatorial region. It will be maximum at the poles. As we go at higher altitudes g value decreases. Same way as we go towards the centre of the earth ie as depth increases, g value decreases.
Anything heavier than water sinks; anything lighter than water floats. Or, another way to say it: anything with a higher density than water (water weighs about a gram per cubic centimeter), or a higher specific gravity than water, sinks. If the object weighs less than the weight of water that it displaces, then it floats.
The strength of the force in each direction between the earth and any mass is called the "weight" of the mass. The force is equal in both directions, which means that the weight of the mass on earth is the same as the earth's weight on the mass. The force acts along the line between the center of the earth and the center of the mass. The direction toward the center of the earth is customarily referred to as the 'down' direction, and toward the center of the mass as the 'up' direction.
It's greater than the density of the surrounding fluid medium. For example, a balloon filled with air sinks in air -- falls to the ground -- but floats in water. For water-tight objects, it is the average density that matters. The buoyant force acting on an object submerged in water is equal to the weight of the water displaced by the object. If the object weighs more than the weight of the water it displaces, it will sink, because the buoyant force will be less than the object's true weight. If it weighs less than the weight of the water displaced, it will float. If it weighs exactly the same as the water it displaces, it is said to have neutral buoyancy and will appear to be and behave as if it were weightless. In other words, its apparent weight will be zero. As discussed in the previous paragraph, if a submerged object sinks, we know it weighs more than the water it displaced. We can therefore conclude that it is denser than water.
If the object sinks or floats depends on mass or weight. The object can be made of the same material, but if the weight is not the same (say if it is heavery than water) it will sink.
Bouyancy is defined as the force on a object submerged in a fluid equal to the difference in weight of the object and the fluid displaced. If the total weight of the object is the same as the same volume of the fluid, the bouyant force is zero, and the object will stay in the same place.
Look at the LAST WORD of the question, they switch it sometimes if it is: Underwater than it is TRUE, If it's Surface of the water than it is FALSE ~
The weight of any object on the Moon is about 1/6 of the weight of the same object on the Earth.
The difference between an object's weight, and the weight of water with the same volume as the object.
Mass b > mass a
the hidden object weight the same as the airplane
The force of gravity between the Earth and an object on its surface is what we call the object's "weight". What is not generally appreciated is that the object attracts the Earth toward it with the same force. This means that whatever your weight is on Earth, it's the same as the Earth's weight on you.
If on object is more dense than water (1 g/ml) it sinks. If it is less it floats. If it is the same it goes up and down.
When an object is immersed in a liquid, the liquid exerts a buoyant force on the object which is equal to the weight of the liquid displaced by the object. This statement is known as Archimedes' Principle. When a solid body is immersed wholly or partially in a liquid, then there is same apparent loss in its weight. This loss in weight is equal to the weight of the liquid displaced by the body. the bouyant force of an object equal to the weight of the fluid that the object displaced .
The weight of an object on the moon's surface is 16.3% of the same object's weight on the earth's surface.
Yes. The mass of an object is always the same, but the weight of an object depends on the force of gravity on it.