why the large ship can float but a steel needle sinks in the water ?

Archimedes' principleindicates that the upwardbuoyant forcethat is exerted on a body immersed in afluid, whether fully or partially submerged, is equal to theweightof the fluid that the bodydisplaces.

By the principle, a ship can displace more water than its weight and hence floats because of a broader base whereas a needle cannot.

{apparent immersed weight} = {weight of object} - {weight of displaced fluid}
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