Question

what is the cause of upthrust

Answer 1

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Answer 2

 

The liquid present in a vessel exerts same kind of pressure at all points in all directions. The depth is directly proportional to the pressure; as the depth increases the pressure also increases. When a block is immersed in a liquid, the liquid exerts an upward pressure which is inversely proportional to the depth; hence the pressure difference between the lower and upper surface of block can be defined as force is equal to pressure into area. This difference of pressure causes a force on the block which is called up thrust or net upward.