Why did the chicken cross the road? Forget the joke, let's talk about how things float in water (like ships & kayaks) and other stuff sinks down (Like stones or cars or nemo.) to the depth of waters like nobody's business.
[Insert Titanic Joke here]
SIDENOTE: Please don't judge Nemo for his capabilities, Nemo don't like that.
OK so, Why don't the ships sink?
Ships float over water even though they are made of steel and Iron. and Iron and Steel are clearly denser than water.
Its due to the buoyant force exerted by the water, the principle behind this is called Archimedes' principle.
Archimedes' principle
Archimedes' principle states that "an upward force that is exerted on a body immersed in a fluid, is equal to the weight of the fluid displaced by the body."
Means when a body is submerged in the fluid. (Water for eg.) an upward force is exerted on it.
Why? because the water wants to rush back to the place and tries to occupy the space.
This force is called Buoyant Force, and it's equal to the weight of the water displaced by the body.
This is the reason why you feel the bucket (Metal bucket) weigh less when submerged into the water because the water is trying to push the bucket up. There's a fight going on between the Buoyant force and the Weight force on the bucket, the stronger one wins. :P
I'm gonna write an equation now. Don't worry I'll be gentle. :P
So, Mathematically we can say that
Effective weight = Weight of the object - Weight of the displaced water
Here, the "Effective weight" is the resultant force acting on the body. (if Effective weight is positive the body will sink, and if its negative body will float to equilibrium.)
hmm, So now if we want the body to float, all we have to do is design the body such way that weight of the displaced water is greater than the weight of the object. there you go, a floating ship.
This is the basic principle behind the floating ship.
Well, this isn't the only way objects float on the water. Ants can also float on water using surface tension. but that's a story for another time. :P
Thanks a lot for reading this post. don't forget to leave a comment. :)
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