Why does a pin that is made up of steel sink in the sea while a ship made of steel floats?

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The density of seawater is more significant and hence the ship floats.

Owing to the large volume of the ship, it displaces more water, so up-thrust is more.

Steel used in a pin has more density than steel used in a ship.

In the case of the tip, the pressure is more since the area of its tip is small, so it sinks, but for the ship, the size of its base is more, therefore it exerts very less pressure.

answer is B.

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Detailed Solution

When an object is placed in a liquid, two forces are acting on the object. One is the weight of the object and the other is the upthrust. Weight is exerted in the downward direction and the upthrust is exerted by the liquid on the object in the upward direction.

The floating and sinking of an object depend on the balancing of these two forces.

An object floats in liquid when the upthrust of the liquid is more than the weight of the object.
An object sinks in liquid when the upthrust is less than the weight of the object.
An object floats just inside the surface of the liquid when the upthrust is equal to the weight of the object.

Upthrust on an object depends on the volume of the object and the density of the liquid. More is the volume of the object, the more the upthrust as it displaces more liquid.

Since the ship displaces far more water than a pin, the upthrust exerted by seawater on the ship is a lot more and outweighs the weight of the ship. Therefore, the ship floats while the pin sinks.

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