Give Reasons for the following :

Will the magnitude of upthrust change when more and more volume of a rigid body is immersed in water? When does this upthrust become minimum?


The upthrust is equal to the weight of water displaced when the object is immersed in it. More the volume of submerged part of rigid body, more is the water displaced and thus more is the upthrust.
When the density of body is equal to the density of the water, the upthrust is minimum because the object just floats.

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