Consequences of Liquid Pressure

Q.

Why do sea divers need special protective suit ?

Q.

Why does the body of a deep sea fish burst on bringing her above the sea level?

1. The body of fish contains dissolved oxygen at much higher pressure than the atmospheric pressure

2. The atmospheric pressure above the sea level is higher than inside the sea.

3. The body of fish contains dissolved oxygen at much lower pressure than the atmospheric pressure

4. The atmospheric pressure above the sea level is lower than inside the sea.

Q.

A dam has broader walls at the bottom than at the top. Explain.

Q.

Explain why a gas bubble released at the bottom of a lake grows in size as it rises to the surface of lake.

Q.

Why army tank weighing more than 1tonnes rests upon a continuous chain

Q. The same force produces less pressure if it acts on a large area but it can produce high pressure if it acts on a small area. Explain .

Q.

Why the pressure on the ground is more when a man is walking than he is standing?

Q. The pressure of water on the ground floor is 40000Pa and on the first floor is 10000 Pa find the height of the first floor. (Take: density of water=1000kg m-3 , g=10m s-2)

Q. Sharp knife and blunt knife application

Q. State the laws of liquid pressure.

Q. How does the liquids pressure on a diver change if:
The diver moves to the greater depth

Q.

Dams are made thicker at the bottom than at the top. Why?

Q.

Calculate the pressure at a depth of 50m below the surface of sea. The density of sea water is 1024 $\frac{kg}{m^3}$.

Q.

A cylindrical vessel containing water at 4^o C, if the cross-section of the vessel is 100 cm², the pressure at a point in water at a depth of 10 cm will be :

(g = 10m/s²)

1. 10³ pa

2. 10⁴ pa

3. 10 pa

4. 10² pa

Q.

Why we are not crushed by the pressure created by a thick layer of atmosphere?

Q.

Calculate the pressure at a depth of 50 m below the surface of the sea. The density of sea water is 1024 kg/m³.

1. 512000 Pa

2. None of these

3. 5120 Pa

4. 51200 Pa

Q. Three containers are used in chemistry lab. All containers have same bottom area and the same height. A chemistry student fills each of the containers with same liquid to the maximum volume. Which of the following is true about the pressure on the bottom for each container?

1. P1>P2>P3
2. P1P3
3. P1
4. P1=P2=P3

Q.

Dams have very broad base. Explain.

Q. When a bubble, released from the bottom of a lake, rises near the water surface, it

1. increases in volume
2. decreases in volume
3. does not change volume
4. decreases in radius

Q. How does the liquids pressure on a diver change if:
The diver moves horizontally?

Q. Kerosene oil rises up in a wick of a lantern because of:

1. diffusion of the oil through the wick
2. buoyant force of air
3. capillary action
4. the gravitational pull of the wick

Q. Why do sea divers need special protective suit ?

Q. There is high pressure on the bottom of sea, then how animals survive?

Q.

When we use a drinking straw, what unbalanced force pushes the liquid up the straw? Explain briefly with the help of a diagram. If there is a small hole in the upper part of the straw what difference does it make, if any?

Q. liquid rising in a capillary tube does not form a fountain if insufficent lenght is available .why?

Q. A perpendicular force is applied to certain area and produces pressure P. If the same force is applied to a twice bigger area, the new pressure on the surface is

1. 2P
2. 4P
3. P
4. P/2

Q. Amount of pressure of liquid increases with

1. volume
2. base area
3. depth
4. mass

Q. Complete the following sentences:
Pressure of a liquid at a given depth is ..........to the density of a liquid.

Q. What is the difference between the pressure on the water surface and that on the bottom?

1. $\rho gh$
2. $\frac{\rho g}{h}$
3. Zero
4. Infinity

Q. Which of the following is/are FALSE:

1. A balloon collapses when air is removed from it.
2. Water does not run out of a dropper unless its rubber bulb is pressed.
3. Two holes are made in a sealed tin can to take out oil from it.
4. None