Assalamoalikum and welcome back to Orange Shots ..
Throw this screw in the water and it would sink ..
Launch a Ship on water and she will float ..
Why a Ship floats and a screw Sinks in the Water
Your answer to the question may be very simple ..
Buoyancy or Simply Upthrust of Sea Water ..
While that answer is correct ..
there are more details to it than you may think ..
A screw is very small,
in fact tiny in comparison to a ship ..
A ship weighs thousands of tonnes ..
For example the weight of our ship is close to 25000
Tonnes when empty and now when she is loaded,
her weight is almost 175000 tonnes and yet she is sailing
across the ocean as if everything is just nice and fine
and nothing Significant is going on ..
Compare that weight to this small screw,
it's weight is hardly a few grams
let alone a Kilogram ..
Being so light and almost weightless ..
throw this in the water and I can promise you that
it will sink in a blink of an eye ..
Buoyancy or upthrust of water is always there
and it acts upon every weight that is either floating,
Submerged or even partially Submerged in the water ..
The weight of the object pushes the object in the water
and buoyancy tries to push it out ..
It's like a tug of war that going on
between weight of an object
and buoyancy of water
once that object is immersed in water.
The question that arises is ..
this buoyancy is acting equally on a ship
and on this small screw ..
and still the ship keeps floating
while the crew would still Sink ...
So definitely there is something more to the answer
than Just the buoyancy of water ..
That is where another thing comes in
and that's called DENSITY ..
Density of anything is defined as weight per unit volume ..
Or in normal Urdu " the weight in kilograms of an object
that can fit inside a m3 of Volume" is called density ..
Just like any other Object in the world, sea water has it's own density ..
Ranging anywhere from 1001 to 1025 kg / m3 ,
Fresh water on the other hand has a density of about 1000 kg/m3,
if you immerse anything that has lesser density in this water ,
it will float on it's top,
If the density of the object that is immersed is higher
in comparison to to the density of water in which it is immersed,
The thing will submerge and Sink.
The classical example is Oil and Honey ..
put some oil in water and it will keep floating on top ..
put some honey in the same Water and the honey would Sink ..
== Density ==
You might be asking yourself then why does Human beings
Sink in the Water ..
Human beings have an average density of 985 kg/m3,
That's much lesser then the density of Fresh Water ..
Technically Human beings Should always be able to float ..
They Should not drown in the water .. at all ..
That's absolutely correct ..
And yes, if you're a swimmer and know how to swim,
you'd also be confident enough to let your body float ..
And human beings - if they're not wearing the type
of clothes that would absorb water,
by design, would in fact never drown in water
if they don't TRY HARD to swim or FLOAT ..
If they'd trust their density and let their body float ..
they will float
Now comes the more complex question ..
Steel that is mostly used on ships is far heavier
and dense than both - the fresh water and sea Water ..
Whether we consider sea water of Fresh Water ..
Yet once it's given the shape of a Ship,
it starts floating,
how is this achieved without lowering the density of steel
and even after loading Thousands of Tonnes on top.
The answer lies in it's clever design that makes it possible ..
To understand this, let's consider a log of Wood,
It floats on top of water,
But if you see closely, very closely,
these logs are partially submerged ..
Slowly people understood one thing that
if by any means they make the log hollow,
some of the submerged portion of this log
will come out of the water ..
Now when this log is hollowed and launched again ..
Not only did the submerged portion reduce, but
You could fill up the hollowed portion with practically anything
as long as it doesn't submerge the whole wooden log
Now this wooden log was able to not only just float ..
but carry our stuff too..
Here - the density of wood didn't change at all -
but by making the log hollow we were able to enable this log
actually carry something for us and yet Float ..
What we did here is we changed the weight of the log
by making it hollow ..
Using the same principle people were able to carve out
bigger boats with wooden hull enabling them
to carry not just goods but people and equipment too ..
Density wasn't changed but giving them an elongated shape
with curved Shell, gives a simulation of lesser density
You feel that its less dense as inside of a hull is empty
that in turn enables a boat to float.
Using the same principle engineers were able to figure out
that even if a heavier steel hull was carved out ..
as long as this hull was long enough and high enough -
Even after partially submerged in water - it will float.
It should long as this hull was long enough to float ..
& High enough to not suberge fully in the water ..
This steel made hull would infact float easily.
If you have a closer look at all steel made ships,
their some portion is always under water,
This underwater portion of a ship increases when cargo is loaded
and decreases when a ship is empty,
but a certain portion of a ship is always under water -
and we call it Draft of a ship.
we measure this portion in Meters and centimetres,
Hence using a clever design,
and by using the dense steel metal plates
to build strong Ships,
we are now able to take advantage of water's upthrust
and hence enable a ship to float.
Humans were able to Build a Ship
Trust me if you'd design this screw clever enough,
it will float too,
but that's not how design and innovation works ..
To make floatable screws
we first have to have a real need
and then some proper usage of the floating screws
There should be a place where we can use them
Only then we will be justified to dedicate our resources ..
& money for developement of the screws
that can float on water.
Until then, any screw thrown in the water
will keep on sinking
and every Ship will keep on floating ..
I seriously hope that I was able to
convey some sort of information
to you people via this video ..
If you have gained some knowledge or
if this video has helped you in any way
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Take Very Good care of yourself and Keep me in your Prayers
With Tonnes of love for my Orange Shots family
and to be Orange Shots family ..
This is Zahid Nisar,
You are watching "Orange Shots"
& Until the next Video .. Allah Hafiz..