2007-04-04 11:30:13 · 6 answers · asked by Crystal Smith 2 in Science & Mathematics ➔ Physics
Imagine you have a thousand pounds of styrofoam. It is heavy, yes, but it will not sink in water. Density determines whether or not an object sinks or floats.
2007-04-04 11:40:25 · answer #1 · answered by Anonymous · 1⤊ 0⤋
If you consider Newton's law and that Eureka guy's law, then you can see why it doesn't matter what they weigh, just how much fluid they can displace.
Like the Eureka guy stated that the upward force acting on an object is equal to the weight of the water that would take up the space that the object is taking up.
So if an object that has a volume os 10cm^3 is halfway in water, then the amoutn of space it is taking up is 5cm^3 and if you wanted the upward force acting on that object, it is equivalent to finding the weight of water that fits in 5cm^3.
And Newton's law says that if an object is not moving (floating counts as not moving), then all the forces acting on it have to add up to 0.
So consider an object floating in water. The weight of that object is acting downwards. And the upward force is equal to the weight of the water in the space that it occupies in the water. If it occupies more space in the water (if it's volume is higher), then the upward force acting on it is higher. So you can add more weight to it and it will still float.
This is why big heavy ships can float, because they do have a huge weight (huge downward force), but the amoutn of space they take up in the water is also huge (huge upward force) and these forces cancel to cause 0 net force on ships.
So the heavier objects are, the more space they need to take up in the water in order to stay floating.
Hope that helps
2007-04-04 11:56:36 · answer #2 · answered by Anonymous · 0⤊ 1⤋
Something will only sink down into the water to the point where it has displaced its own weight in water. So, anything can float as long as it has enough volume to displace its own weight in water before it is fully submerged.
2007-04-04 11:42:58 · answer #3 · answered by Adam S 4 · 1⤊ 1⤋
Weight is irrelevant; density is what matters. The greater the mass, the greater the required volume for the object to float.
2007-04-04 11:44:07 · answer #4 · answered by Anonymous · 1⤊ 0⤋
ships dont sink they weigh a ton..i am thinking because they are built to not let any water in..and they are full of air
2007-04-04 11:38:08 · answer #5 · answered by bailie28 7 · 0⤊ 1⤋
It depends on how much water they displace. Metal ships float because of their shape.
2007-04-04 11:36:42 · answer #6 · answered by Gene 7 · 1⤊ 1⤋