CBSE Worksheet for chapter7 Fluid class 9
Worksheet For class 9
Find CBSE Worksheet for chapter7 Fluid class 9
CLASS9
BOARD: CBSE
Physics Worksheet  7
TOPIC: Fluid
For other CBSE Worksheet for class 9 Science check out main page of Physics Wallah.
SUMMARY
 Fluids,Pressure in fluids, Thrust, Units of pressure
 Buoyancy force, Factors affecting buoyant force
 Archimedes principle, Relative density, Uses of Archimedes principle
 Physical meaning of relative density, Law of floatation
SECTION I – OBJECTIVE

If a force of 10 N acts perpendicularly on two surfaces (area in the ratio 1:2), then the ratio of thrust will be:
 1:2
 2:1
 3:1
 1:1

A force of 50 N is applied normally on a nail of area 0.001 sq.cm. Then the thrust is:
 50 N
 100 N
 0.05 N
 10 N

Pressure cannot be measured in:
 N/m^{2 }
 bar
 Pa
 kg.wt

Pressure is:
 Scalar quantity.
 Normal force
 Vector quantity
 All the above are wrong

The atmosphere exerts a pressure of P on the surface of the earth, then P equals to:
 1.01x10^{5} N/m^{2 }
 1.01x10^{5} N/m^{2 }
 1.01x10^{7} N/m^{2 }
 1.01x10^{7} N/m^{2}

Unit of relative density is:
 kg/m^{3 }
 g/m^{3}
 g/litre
 Unit less

A cylinder of wood floats vertically in water with onefourth of its length out of water The density of wood is:
 0.25 g/cm^{3}
 0.5 g/cm^{3 }
 0.75 g/cm^{3 }
 1 g/cm^{3}

Two solids X and Y float on water, X floats with half of its volume submerged while Y floats with onethird of its volume out of water. The densities of X and Y are in the ratio of:
 4:3
 3:4
 2:3
 1:3

Archimedes principle is used to:
 Design ships
 Design Submarines
 Design Lactometers
 All of them

As we move upwards, the atmospheric pressure:
 Increases
 Decreases
 Remains same
 cannot be said
SECTION II  SUBJECTIVE

Explain following terms:
 Fluid
 Pressure in fluid
 Thrust
 State Archimedes principle.
 What is the pressure due to man weighing 80 kg, standing on his feet? Area of his feet= 160 sq cm.
 (g = 10 m/s^{2})
 What is height of mercury which exerts the same pressure as 20 cm of water column?
 Take density of mercury as 13.6 g/cc.
 When an aluminium object is immersed in water, it displaces 5 kg of water.
 How much is the buoyant force acting on the aluminium object in newtons? (g= 10 m/s^{2})
 The relative density of silver is 10.5. The density of water is 10^{3} kg/m^{3}. What is the density of silver in S.I. unit?
 A body of volume 300 cm^{3} and relative density 1/3 is placed in water. Will it sink or float in water and what will be the volume of water displaced by it?.
Solutions: to worksheet7 Fluid
Objective Problems:
1.(D)  2.(A)  3.(D)  4.(A)  5.(A)  6.(D)  7.(C)  8.(B)  9.(D)  10.(B) 
Subjective Problems :
 5x10^{4} N/m^{2}
 1.48 cm.
 50 N
 d_{Ag }= 10.5x10^{3} kg/m^{3}

Float, Volume = 100cm^{3}