Torr is the unit of pressure, which is defined as the magnitude of force acting perpendicular to the surface of an object per unit surface area of the object. One torr is the pressure exerted by 1 mm of mercury column. 1 Torr = 133 . 3 Pa

MEDIUM

Earn 100

The height of mercury column in a simple barometer is $h$ . As the tube is inclined with the vertical at an angle $α$ , then length of mercury column along the length of the tube will become

50% studentsanswered this correctly

Important Questions on Thrust and Pressure

HARD

Science>Physics>Thrust and Pressure>Pascal's Law

An open-ended U-tube of uniform cross-sectional area contains water (density $10^{3} kg m^{- 3}$ ). Initially the water level stands at $0.29 m$ from the bottom in each arm. Kerosene oil (a water-immiscible liquid) of density $800 kg m^{- 3}$ is added to the left arm until its length is $0.1 m$ , as shown in the schematic figure below. The ratio $(\frac{h_{1}}{h_{2}})$ of the heights of the liquid in the two arms is

Question Image

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

In a hydraulic lift, compressed air exerts a force

F

on a small piston of radius

3 cm

. Due to this pressure the second piston of radius

5 cm

lifts a load of

1875 kg

. The value of

F

is
(Acceleration due to gravity

= 10 m s^{- 2}

)

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R

Assertion A: When you squeeze one end of a tube to get toothpaste out from the other end, Pascal’s principle is observed.

Reason R: A change in the pressure applied to an enclosed incompressible fluid is transmitted undiminished to every portion of the fluid and to the walls of its container.

In the light of the above statements, choose the most appropriate answer from the options given below.

HARD

Science>Physics>Thrust and Pressure>Pascal's Law

Two narrow bores of diameter

5.0 mm

and

8.0 mm

are joined together to form a

U -

shaped tube open at both ends. If this

U -

tube contains water, what is the difference in the level of two limbs of the tube.
[Take surface tension of water

T = 7.3 \times 10^{- 2} N m^{- 1}

, angle of contact

= 0, g = 10 {m s}^{- 2}

and density of water

= 1.0 \times 10^{3} kg m^{- 3}]

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

One ton stone is put on a larger piston of diameter

40 cm

of a hydraulic lift and a pressure

P

has to be applied on the smaller piston of diameter

2 cm

, to lift the stone. The pressure

P

, is approximately

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

A hydraulic press can lift

100 kg

when a mass

m

is placed on the smaller piston.How much mass (in

k g

) can it lift when the diameter of the larger piston is increased by

4

times and that of the smaller piston is decreased by

4

times keeping the same mass

m

on the smaller piston.

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

The working of hydraulic lift is based on the principle of

HARD

Science>Physics>Thrust and Pressure>Pascal's Law

Consider a vessel filled with a liquid upto height

H .

The bottom of the vessel lies in the

X - Y

plane passing through the origin. The density of the liquid varies with

Z

-axis as

ρ (z) = ρ_{0} [2 - {(\frac{z}{H})}^{2}]

. If

P_{1}

and

P_{2}

are the pressures at the bottom surface and top surface of the liquid, the magnitude of

(P_{1} - P_{2})

is :

MEDIUM

Science>Physics>Thrust and Pressure>Pascal's Law

U

tube with both ends open to the atmosphere is partially filled with water. Oil, which is immiscible with water, is poured into one side until it stands at a distance of

10 mm

above the water level on the other side. Meanwhile, the water rises by

65 mm

from its original level (see diagram). The density of the oil is ____

(ρ_{w} = 1000 kg m^{- 3})

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

What does a barometer measure?

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

At what speed will the velocity of a stream of water be equal to

20 c m

of mercury column? (Taking,

g = 10 m s^{- 2}

)

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

If pressure at half the depth of a lake is equal to

\frac{2}{3}

times the pressure at the bottom of the lake, then what is the depth of the lake?

MEDIUM

Science>Physics>Thrust and Pressure>Pascal's Law

Would you be able to suck juice with a drinking straw on the moon? Give a reason for your answer.

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

Find density of ethyl alcohol

Question Image

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

What is torr?

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

A cubical sealed vessel with edge

L

is placed on a cart, which is moving horizontally with an acceleration

‘ a ’

as shown in figure. The cube is filled with an ideal fluid having density

d

. The gauge pressure at the centre of the cubical vessel is -

Question Image

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

The pressure at depth

h

below the surface of a liquid of density

ρ

open to the atmosphere is

EASY

Science>Physics>Thrust and Pressure>Pascal's Law

Torricelli's barometer used mercury. Pascal duplicated it using French wine of density $984 kg m^{- 3}$ . The height of the wine column for normal atmospheric pressure is

MEDIUM

Science>Physics>Thrust and Pressure>Pascal's Law

By sucking through a straw, a student can reduce the pressure in his lungs to

750 mm of Hg

(density

= 13.6 g {c m}^{- 3})

. Using the straw, he can drink water from a glass upto a maximum depth of

MEDIUM

Science>Physics>Thrust and Pressure>Pascal's Law

_____ is a device used to measure the pressure exerted by liquids.

The height of mercury column in a simple barometer is h. As the tube is inclined with the vertical at an angle α, then length of mercury column along the length of the tube will become

Important Questions on Thrust and Pressure

Learn and Prepare for any exam you want !

The height of mercury column in a simple barometer is $h$ . As the tube is inclined with the vertical at an angle $α$ , then length of mercury column along the length of the tube will become