physics MCQs - 11th class Chapter 04 Mcqs

1

Work is a product of the magnitude of displacement and the component of the force in the direction of the displacement. This is represented by the formula:

A

W = Fd

B

W = Fd sin θ

C

W = Fd cos θ

D

W = F/d

2

What is the SI unit of work?

A

Watt

B

Newton

C

Pascal

D

Joule

3

Work done is considered negative when the angle θ between the force and displacement is:

A

θ < 90°

B

θ > 90°

C

θ = 90°

D

θ = 0°

4

When the force and displacement are perpendicular to each other, the work done is:

A

Maximum

B

Minimum

C

Zero

D

Negative

5

The area under a force-displacement graph represents:

A

Power

B

Energy

C

Work

D

Force

6

A field in which the work done is independent of the path followed is called a:

A

Gravitational Field

B

Electric Field

C

Magnetic Field

D

Conservative Field

7

Which of the following is an example of a non-conservative force?

A

Gravitational force

B

Elastic spring force

C

Frictional force

D

Electric force

8

Power is defined as the rate of doing work. Its formula is:

A

P = W * t

B

P = W / t

C

P = F / t

D

P = F * d

9

The SI unit of power is:

A

Joule

B

Kilowatt-hour

C

Watt

D

Newton-meter

10

One kilowatt-hour (kWh) is equal to:

A

3.6 J

B

3.6 x 10^3 J

C

3.6 x 10^6 J

D

36 x 10^6 J

11

The relationship between power, force, and velocity is given by:

A

P = F / v

B

P = F.v

C

P = F + v

D

P = F - v

12

The energy possessed by a body due to its motion is called:

A

Potential Energy

B

Kinetic Energy

C

Elastic Energy

D

Chemical Energy

13

The formula for kinetic energy is:

A

K.E. = mv

B

K.E. = 2mv^2

C

K.E. = mgh

D

K.E. = 1/2 mv^2

14

The work-energy principle states that the work done on a body equals the change in its:

A

Potential Energy

B

Momentum

C

Kinetic Energy

D

Velocity

15

The formula for gravitational potential energy near the Earth's surface is:

A

P.E. = mgh

B

P.E. = 1/2 mv^2

C

P.E. = Fd

D

P.E. = -GMm/r

16

The absolute potential energy of an object at infinity is considered to be:

A

Maximum

B

Infinite

C

One

D

Zero

17

The formula for absolute gravitational potential energy at a distance r from the Earth's center is:

A

U = GMm/r

B

U = -GMm/r^2

C

U = -GMm/r

D

U = mgh

18

The initial velocity required for an object to escape the Earth's gravitational field is known as:

A

Terminal Velocity

B

Orbital Velocity

C

Escape Velocity

D

Critical Velocity

19

The value of escape velocity from the Earth's surface is approximately:

A

9.8 m/s

B

11 km/s

C

8 km/s

D

30 km/s

20

The Law of Conservation of Energy states that energy:

A

Can be created but not destroyed

B

Can be destroyed but not created

C

Can neither be created nor destroyed

D

Is always constant in one form

21

In the presence of friction, the loss in potential energy of a falling body is equal to:

A

Gain in K.E.

B

Work done against friction

C

Gain in K.E. + Work done against friction

D

Loss in K.E.

22

The gravitational force of the ____ gives rise to tides in the sea.

A

Sun

B

Earth

C

Moon

D

Jupiter

23

Salter's duck is a device used to harness energy from:

A

Tides

B

Sun

C

Wind

D

Waves

24

The solar constant, which is the solar energy at normal incidence outside the Earth's atmosphere, is about:

A

1.0 kWm⁻²

B

1.4 kWm⁻²

C

2.0 kWm⁻²

D

0.8 kWm⁻²

25

Solar cells, which convert sunlight directly into electricity, are also known as:

A

Photoelectric cells

B

Electrolytic cells

C

Photovoltaic cells

D

Galvanic cells

26

Which material are solar cells typically made from?

A

Copper

B

Germanium

C

Silicon

D

Carbon

27

All the organic materials such as crop residue, trees, and animal dung are collectively known as:

A

Fossil Fuels

B

Biomass

C

Geothermal sources

D

Biofuel

28

The process of obtaining energy from waste products by burning them in a confined container is called:

A

Fermentation

B

Direct combustion

C

Decomposition

D

Gasification

29

The heat energy extracted from inside the Earth is known as:

A

Solar Energy

B

Biomass Energy

C

Geothermal Energy

D

Nuclear Energy

30

A hot spring that intermittently discharges steam and hot water is called a:

A

Volcano

B

Aquifer

C

Geyser

D

Fumarole

31

Work done is a ____ quantity.

A

Vector

B

Scalar

C

Fundamental

D

Derived

32

A kilowatt-hour is the unit of ____.

A

Power

B

Force

C

Energy

D

Pressure

33

According to the work-energy principle, Fd = ?

A

1/2 mv_f^2 - 1/2 mv_i^2

B

mgh_f - mgh_i

C

mv

D

ma

34

The escape velocity is directly proportional to the square root of:

A

Mass of the body

B

Radius of the Earth

C

Mass of the Earth

D

Gravitational constant

35

For a freely falling body, the sum of P.E. and K.E. is always:

A

Increasing

B

Decreasing

C

Zero

D

Constant

36

The energy stored in a compressed spring is an example of:

A

Kinetic Energy

B

Gravitational Potential Energy

C

Elastic Potential Energy

D

Chemical Energy

37

The original source of energy for fossil fuels is the:

A

Earth

B

Moon

C

Sun

D

Stars

38

The formula for escape velocity in terms of g and R is:

A

v_esc = sqrt(gR)

B

v_esc = sqrt(2gR)

C

v_esc = gR

D

v_esc = 2gR

39

In a tidal power plant, turbines are driven by:

A

Wind

B

Steam

C

Moving water

D

Burning fuel

40

On a clear day at noon, the intensity of solar energy reaching the Earth's surface is about:

A

1.4 kWm⁻²

B

1.0 kWm⁻²

C

0.5 kWm⁻²

D

2.0 kWm⁻²

41

A layer of rock holding water that allows water to percolate through it with pressure is called an:

A

Igneous rock

B

Aquifer

C

Magma

D

Geyser

42

What is the work done when a 50 kg bag is lifted through 50 cm? (g=10 m/s²)

A

25 J

B

250 J

C

2500 J

D

2.5 J

43

Power is a scalar product of:

A

Force and displacement

B

Force and time

C

Force and velocity

D

Mass and velocity

44

The absolute potential energy on the Earth's surface is given by U_g = -GMm/R. The negative sign indicates that the field is:

A

Repulsive

B

Weak

C

Non-conservative

D

Attractive

45

The conversion of biomass into fuels like ethanol is typically done through:

A

Direct combustion

B

Fermentation

C

Melting

D

Distillation

46

In a flat-plate solar collector, the surface is blackened to:

A

Reflect energy

B

Absorb energy

C

Reduce weight

D

Insulate

47

What is the work done in pushing a crate 2m across a floor with a force of 50 N?

A

25 J

B

52 J

C

100 J

D

200 J

48

When an object is moved against the gravitational force, the work done by the gravitational force is:

A

Positive

B

Negative

C

Zero

D

Infinite

49

The energy of a body by virtue of its position in a field is called:

A

Kinetic Energy

B

Mechanical Energy

C

Potential Energy

D

Heat Energy

50

Which of these is a renewable source of energy?

A

Coal

B

Natural Gas

C

Uranium

D

Wind