An iceberg of density 900 kg/${\mathrm{m}}^3$ is floating in water of density 1000 Kg/${\mathrm{m}}^3$. The percentage of volume of ice-cube outside the water is: 
1. 20%                                       
2. 35%
3. 10%                                       
4. 25%

If two iron balls when fully immersed in water experience thrust force in the ratio of 1:2, then the ratio of the masses of the balls will be:
1. 1: 1
2. 1: 2
3. 2: 1
4. 1: 4

When a man sits on a boat of length 2 m and breadth 1 m floating on a lake, the boat sinks by 2 cm. The mass of the man is:

1. 25 kg

2. 40 kg

3. 60 kg

4. 80 kg

A body of density 0.7 gm/${\mathrm{cm}}^3$ floats on a lake of water. The fraction of the body which is outside water is-

1. 30%

2. 70%

3. 25%

4. 50%

A block weighs 5 N in air and 4.5 N in a liquid of specific gravity 0.5. Its weight in water will be:

1. 3.5 N

2. 4.0 N

3. 2.5 N

4. 3.0 N

The reading of a spring balance when a block is suspended from it in the air is 60 N. This reading is changed to 40 N when the block is submerged in water. The specific gravity of the block, therefore, must be:
1. 3
2. 2
3. 6
4. 3/2

A beaker full of water is placed on a spring balance. If we put our finger in water without touching the beaker, how will the reading of the balance change? [Take ${\mathrm{\rho }}_{\mathrm{finger}}$ $>$ ${\mathrm{\rho }}_{\mathrm{water}}$]
1. Increase
2. Decrease
3. Remain the same
4. Will be halved

 Two non-mixing liquids of densities $\rho$ and n$\rho$(n>1) are put in a container. The height of each liquid is h. A solid cylinder  floats with its axis vertical and length pL $\left(p<1\right)$ in the denser liquid. The density of the cylinder is d. The density d is equal to:

1. {2+(n+1)p}$\rho$             

2. {2+(n-1)p}$\rho$

3. {1+(n-1)p}$\rho$             

4. {1+(n+1)p}$\rho$

If two pieces of metal when immersed in a liquid have equal upthrust on them, then:

A boat carrying steel balls is floating on the surface of water in a tank. If the balls are thrown into the tank one by one, how will it affect the level of water?