## Question

*S*_{1} and *S*_{2} are spring balances. A block *A* is hanging from spring balance*S*_{1} 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 *S*_{1} and *S*_{2}balances reads 2.5 kg and 7.5 kg respectively. What will be the reading of*S*_{1} and *S*_{2} when the block *A* is pulled up out of the liquid :

### Solution

*S*_{1} will read 2.5 kg and *S*_{2} will read 7.5 kg

When a body is immersed in a liquid, its experiences an up thrust *u*. Which make spring balance *S*_{1} to read

Apparent weight = true weight – up thrust

= *w _{A}* –

*u*= 2.5 kg

*S*_{2} reads :

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

#### SIMILAR QUESTIONS

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