Laws of Liquid Pressure

Q.

Which liquid has highest density?

Q.

State the laws of liquid pressure.

Q.

What is one atmosphere?

Q.

The pressure $P_1$ at the top of a dam and $P_2$ at a depth $h$ from the top are related as:

1. $P_1>P_2$

2. $P_1=P_2$

3. $P_1-P_2=\rho gh$

4. $P_2-P_1=\rho gh$

Q.

Arrange the following in the increasing order of their relative densities.

Iron, air, ice, water, aluminum.

Q.

If the atmospheric pressure is ${10}^5\frac{N}{m^2}$ and the density of water ${10}^3\frac{kg}{m^3}$. What will be the depth below the surface of water if pressure is equal to thrice the atmospheric pressure?

1. 10² m

2. 20 m

3. 30 m

4. 10 m

Q. Describe a simple experiment to demonstrate that a liquid enclosed in a vessel exerts pressure in all directions.

Q.

In a pond, the pressure at the surface at point A is P${}_1$ and at another point B, which is h meter below A is P ${}_2$. Which of the following statements holds true?

1. P${}_1$ >P${}_2$

2. P${}_2$ >P${}_1$

3. P${}_2$ = hρg + P${}_1$

4. P${}_1$ = hρg + P${}_2$

Q. A thin square plate of side $4m$ is placed horizontally $2m$ below the surface of water. Calculate the thrust on one of the surface of the plate.
(Given: Atmospheric pressure, $P_{atm}=1.013\times {10}^{5}N/m^2$
Density of water, ${\rho }_w$ = $1000kg/m^3$,
Acceleration due to gravity, $\left(g\right)=9.8m{s}^{-1}$)

Q. The following figure shows a body floating in three different liquids A, B, and C at different levels.

Which liquid has the least density?

1. Liquid A
2. Liquid B
3. Liquid C
4. All have the same density

Q.

A piece of iron has a weight of 3.5 N when it is in air and 2.0 N when it is submerged into water. What is the buoyant force on the piece of iron?

1. 1.0 N
2. 3.5 N
3. 2.0 N
4. 1.5 N

Q.

Pressure at a point in the liquid is:

1. unequal in all directions

2. equal in all directions

3. greater in an upward direction

4. greater in a downward direction

Q. A thin square plate of side $4m$ is placed horizontally $2m$ below the surface of water. Calculate the thrust on one of the surface of the plate.
(Given: Atmospheric pressure, $P_{atm}=1.013\times {10}^{5}N/m^2$
Density of water, ${\rho }_w$ = $1000kg/m^3$,
Acceleration due to gravity, $\left(g\right)=9.8m{s}^{-1}$)

Q.

Liquids of densities d1 and d2 mixed in equal volume result in a density of 4 and if mixed in equal masses results in a density of 3.

1. Then d1 = 6 and d2 = 2

2. Then d1 = 3 and d2=5

3. Then d1 = 12 and d2=4

4. None of these

Q. We have observed that water leaking from a pipe forms fountains. What conclusion can you draw from this observation?

1. Water exerts pressure on walls of the pipe.
2. Water does not exert pressure on walls of the pipe.
3. Water exerts pressure in the middle of the pipe only.
4. Water pressure decreases with an increase in density of the liquid.

Q. If $P_1$ and $P_2$ are pressures at two points in the liquid at elevations $x_1$ and $x_2$, respectively, and $\rho$ is the density of the liquid, then:

1. $P_1-P_2=\rho g(x_2-x_1)$
2. $P_1-P_2=\rho g(x_1-x_2)$
3. $P_1+P_2=-\rho g(x_2-x_1)$
4. $P_1+P_2=-\rho g(x_1-x_2)$

Q. State the laws of liquid pressure?

Q. The pressure is ______ at a point in a liquid.

1. same in all directions
2. greater towards the up
3. greater towards the down
4. always changing

Q. Calculate the approximate height (h) of Earth's atmosphere extending above the surface of the Earth, assuming the density of air to be uniform [$1.3kg{m}^{-3}$] and pressure at the surface of Earth to be ${10}^{5}Pa$. (Assume the Earth to be perfectly spherical and no variation in 'g' due to height).

1. $5km<h<6km$

2. $7km<h<8km$

3. $8km<h<9km$

4. $6km<h<7km$