Mechanical Engineering
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# why it is easy to pick cotton of 20kg and hard to pick steel of 20kg?

## Question

why it is easy to pick cotton of 20kg and hard to pick steel of 20kg?

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It is because of the fact that more area less pressure.

Pressure = Force/Area

while picking up 20kg iron it concentrate it load on small area giving more pressure to the body.

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It because steel more heavy than the cotton haha

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bcz  the density is high in  steel than cotton

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THEY HAVE THE SAME MASS...BUT DIFFERENT DENSITY....MASS IS THE QUANTITY OF MATTER INSIDE THE SUBSTANCE...BUT STEEL AND COTTON HAVE DIFFERENT DENSITY

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It depends on the shape of steel if you are lifting a ball it will be hard but if you are lifting a plate of steel it will be a lot easier.

Because than the force will be spread on a area larger than the area affected by the ball.

Pressure=force ×area???

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The mass (20kg) is the same. But the volume is different. Thus it displaces different amounts of air. That is, they are differently subject to buoyancy forces caused by immersion in the air. The actual difference can be computed by:

Volume of 20 Kg of cotton - Volume of 20Kg of steel = Delta volume

Delta volume (m3) x density of the air (kg/m3) = Difference of weight

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i think both are the same not cotton easier than steel

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Hello everyone, its very simple.. According to me any thing we are holding which we can shape as per our comfort is the easiest thing to hold...

If we are holding cotton for a long time and now if we want to hold in some other way we can easily adjust with our comfort by pressing or stretching it..but in case of steel we can't adjust its shape as per our varying requirement and hence it becomes hard to hold it...that's all...

Thank you!

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my simple answer is what you mention first (cotton). besides, most people is attracted to characteristics (cotton = white, light, soft; steel = brown due to rust, heavy, hard).

This is also same with the question which comes first, egg or chicken? egg - because it was mention first.

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i think due to density

steel have more mass tan cotton in unit volume

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Both are of the same weight ..so 20kg of cotton will just be the same to pick as to 20kg of steel

On 10/31/2015, 6:18:49, 100rabh said:

Hello everyone, its very simple.. According to me any thing we are holding which we can shape as per our comfort is the easiest thing to hold...

If we are holding cotton for a long time and now if we want to hold in some other way we can easily adjust with our comfort by pressing or stretching it..but in case of steel we can't adjust its shape as per our varying requirement and hence it becomes hard to hold it...that's all...

Thank you!

there is always three side to a story question or argument..your side of the story ,my side of the story and the truth...but above all the truth matters

On 10/18/2015, 3:20:26, Jayson Ramos Tiempo said:

THEY HAVE THE SAME MASS...BUT DIFFERENT DENSITY....MASS IS THE QUANTITY OF MATTER INSIDE THE SUBSTANCE...BUT STEEL AND COTTON HAVE DIFFERENT DENSITY

please what the formular for lift incorporate it to this subject mater

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in this case the mass is same for both

1.the density is not same

2. Volume of 20 Kg of cotton - Volume of 20Kg of steel = Delta volume

and another point is

mass is same but weight is not same

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• -1

The air, much as any fluid, produces lift! And it gets into cotton and affects every fiber of it.

Now, I'd bet if someone made super-thin steel wool, it would be much easier to lift.

The catch here is that this measuring of 20kg has to be done by measuring volume (and calculating mass via density) OR the cotton has to be compressed while it's being measured. This is in order to prevent the force of lift from affecting the measurement.

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