physics MCQs - 9th class Chapter 06 Mcqs

1

A force that changes the shape or size of an object is called a?

A

Restoring force

B

Deforming force

C

Centripetal force

D

Frictional force

2

The property of a body to restore its original size and shape after the deforming force is removed is called?

A

Plasticity

B

Rigidity

C

Elasticity

D

Ductility

3

According to Hooke's law, the extension in a spring is directly proportional to the?

A

Applied force

B

Mass of the spring

C

Length of the spring

D

Density of the spring

4

The SI unit for the spring constant (k) is?

A

N m

B

N m²

C

N m⁻¹

D

N

5

The slope of a force-extension graph for a spring represents the?

A

Work done

B

Extension

C

Applied force

D

Spring constant

6

If a material is deformed beyond its elastic limit, the deformation becomes?

A

Temporary

B

Reversible

C

Permanent

D

Zero

7

Which of the following is an application of Hooke's Law?

A

Hydraulic press

B

Barometer

C

Spring scale

D

Manometer

8

The back and forth motion that regulates the speed of the hands in a mechanical clock is controlled by the?

A

Galvanometer

B

Mainspring

C

Balance wheel

D

Pendulum

9

Density is defined as?

A

Volume per unit mass

B

Mass per unit volume

C

Force per unit area

D

Weight per unit volume

10

The SI unit of density is?

A

g cm⁻³

B

kg m⁻²

C

kg m⁻³

D

g m⁻³

11

Which of the following materials has a very low density according to the text?

A

Steel

B

Water

C

Packing foam

D

Lead

12

Pressure is defined as the normal force acting per unit?

A

Volume

B

Length

C

Mass

D

Area

13

The SI unit of pressure, Pascal (Pa), is equivalent to?

A

N m²

B

N m⁻²

C

kg m⁻³

D

J m⁻¹

14

Pressure within a liquid increases with an increase in?

A

Surface tension

B

Viscosity

C

Depth

D

Temperature

15

The formula for pressure at a depth 'h' in a liquid of density 'ρ' is?

A

P = ρgh²

B

P = ρg/h

C

P = ρh/g

D

P = ρgh

16

As altitude increases, atmospheric pressure?

A

Increases

B

Decreases

C

Remains constant

D

Becomes zero

17

The standard atmospheric pressure at sea level is approximately?

A

1.013 x 10³ Pa

B

1.013 x 10⁵ Pa

C

1.013 x 10⁴ Pa

D

1.013 x 10⁶ Pa

18

Which instrument is used to measure atmospheric pressure?

A

Manometer

B

Galvanometer

C

Barometer

D

Speedometer

19

A fall in atmospheric pressure in a region often indicates?

A

Clear weather

B

Upcoming rain

C

A rise in temperature

D

High winds

20

Pascal's law is applicable to?

A

Solids only

B

Unconfined gases

C

Enclosed fluids

D

Plasma

21

A hydraulic press works on the principle of?

A

Hooke's Law

B

Archimedes' Principle

C

Bernoulli's Principle

D

Pascal's Law

22

A hydraulic system that uses a small force to produce a large force is known as a?

A

Force reducer

B

Force multiplier

C

Work multiplier

D

Energy converter

23

In a hydraulic press, the pressure applied to the small piston is ______ the pressure on the large piston.

A

less than

B

greater than

C

equal to

D

the square of

24

The fluid commonly used in hydraulic brake systems is?

A

Water

B

Mercury

C

Alcohol

D

Oil

25

When a spring is compressed, it stores which form of energy?

A

Kinetic

B

Potential

C

Internal

D

Heat

26

Materials like clay dough that do not return to their original shape are known as?

A

Elastic materials

B

Inelastic materials

C

Brittle materials

D

Ductile materials

27

A spring with a high value of spring constant 'k' is said to be?

A

Softer

B

Longer

C

Stiffer

D

Weaker

28

In a weighing machine using a compression balance, what is measured?

A

The extension produced

B

The compression produced

C

The original length

D

The mass directly

29

What provides the electrical connections and restoring force in a galvanometer?

A

Balance wheel

B

Hair spring

C

Main spring

D

Coil wire

30

The density of water in SI units is?

A

1 g cm⁻³

B

100 kg m⁻³

C

1000 kg m⁻³

D

10 kg m⁻³

31

The density of iron is approximately?

A

2700 kg m⁻³

B

7800 kg m⁻³

C

11400 kg m⁻³

D

19300 kg m⁻³

32

A force acting normally on a surface of area A exerts a pressure P, given by the formula?

A

P = F × A

B

P = A / F

C

P = F / A

D

P = F² × A

33

The sharp edge of a chopper cuts objects easily because it creates a very high?

A

Force

B

Area

C

Pressure

D

Temperature

34

Forces in a liquid that contribute to pressure are always ______ to the surface.

A

parallel

B

at a 45-degree angle

C

perpendicular

D

opposite

35

The layer of air that surrounds the Earth is called the?

A

Hydrosphere

B

Lithosphere

C

Atmosphere

D

Ionosphere

36

At a height of about 30 km, the atmospheric pressure falls to about?

A

100 kPa

B

55 kPa

C

10 kPa

D

1 kPa

37

A simple mercury barometer uses a glass tube about ______ long.

A

10 cm

B

50 cm

C

1 metre

D

2 metres

38

A device used to measure the pressure of a gas in a cylinder is a?

A

Barometer

B

Hydrometer

C

Manometer

D

Calorimeter

39

The main reason liquids are used in hydraulic systems is their?

A

Low density

B

High viscosity

C

Incompressibility

D

Color

40

The force of friction between the brake pads and brake drums causes the vehicle to?

A

Accelerate

B

Turn

C

Slow down

D

Maintain speed