S1 and S2 are spring balances. A block A is hanging from spring balanceS1 and immersed in a liquid L which is contented a beaker B. The mass of beaker B is 1 kg and the mass of liquid L is 1.5 kg. The S1 and S2balances reads 2.5 kg and 7.5 kg respectively. What will be the reading ofS1 and S2 when the block A is pulled up out of the liquid :  


Correct option is

S1 will read 2.5 kg and S2 will read 7.5 kg


When a body is immersed in a liquid, its experiences an up thrust u. Which make spring balance S1 to read

Apparent weight = true weight – up thrust 

  = wA – u = 2.5 kg  

S2 reads : 

    weight of B + weight of L + reaction = up thrust of A   









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