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**Short Answer Type Questions**

**Q.1. An object weighs 10 N in air. When immersed fully in water, it weighs 8 N. The weight of the liquid displaced by the object will be:****(a) 2 N****(b) 8 N****(c) 10N****(d) 12 N****Ans: **Weight in water = 8 N,

Weight in air - 10 N

Weight of liquid displaced = Loss in weight

= 10 N - 8 N = 2 N**Q.2. An object is put one by one in three liquids having different densities. The object floats with 1/9, 2/11 and 3/7 parts of their volumes outside the liquid surface in liquids of densities d _{1}, d_{2} and d_{3} respectively. Which of the following statement is correct?**

Volume of solids immersed = 1 - (1/9),

1 - (2/11) and 1 - (3/7) respectively,

i.e. 8/9, 9/11 and 4/7 respectively.

As V_{1} > V_{2} > V_{3}, the densities of liquids are in magnitude d_{1} < d_{2} < d_{3} This is because, lesser the volume of solid immersed, more is the upthrust acting on it and hence, greater is the density of fluid.

**Q.3. (a) A cube of side 5 cm is immersed in water and then in saturated salt solution. In which case will it experience a greater buoyant force? If each side of the cube is reduced to 4 cm and then immersed in water, what will be the effect on the buoyant force experienced by the cube as compared to the first case? Give reason for each case.****(b) A ball weighing 4 kg of density 4000 kgm ^{-3} is completely immersed in water of density 10^{3} kgm^{-3}. Find the force of buoyancy on it. (Given g = 10 ms^{-2})**

(b) Given: Mass of ball = 4 kg,

Density of ball = 4000 kg/m

Diversity of water = 10

Volume of ball, V

= 10

Upthrust, U = Vρg = 10

= 10 N

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