CHAPTER 8

Question 1

What factor primarily determines the speed of sound in a material?

Answer 1

Density and elasticity of the medium

Question 2

What is a major difference between conduction and convection as modes of heat transfer?

Answer 2

Convection involves bulk movement of particles

Question 3

Which of the following represents an energy transformation rather than an energy transfer?

Answer 3

Light energy converted to chemical energy during photosynthesis

Question 4

In a hydrogen fuel cell, what energy transformation takes place?

Answer 4

Chemical to electrical

Question 5

Why does the pitch of an ambulance siren appear to decrease after it passes you?

Answer 5

The frequency decreases as the source moves away

Question 6

Which characteristic of a material most affects its thermal conductivity?

Answer 6

Atomic structure and free electrons

Question 7

A photovoltaic cell primarily converts which form of energy?

Answer 7

Electromagnetic to electrical

Question 8

In terms of energy transformation, what sequence best describes hydroelectric power
generation?

Answer 8

Gravitational → Kinetic → Mechanical → Electrical

Question 9

Which statement about nuclear fusion in the Sun is correct?

Answer 9

It fuses hydrogen atoms, releasing large amounts of energy

Question 10

In energy terms, what makes uranium-235 an efficient fuel source?

Answer 10

It has a high specific energy due to mass-energy conversion

Question 11

What process turns nuclear energy into usable electricity?

Answer 11

Steam turbine rotation

Question 12

What primarily drives the rate of thermal energy transfer?

Answer 12

Temperature difference

Question 13

When did the emergence of man approximately occur?

Answer 13

4,000,000 B.C.

Question 14

What directly affects wind energy conversion rate?

Answer 14

Wind speed and air density

Question 15

The modern steam engine was developed in:

Answer 15

1765 A.D.

Question 16

What regulates the rate of nuclear energy conversion?

Answer 16

Number of reactions per second

Question 17

What is the unit commonly used to measure the rate of electrical energy conversion?

Answer 17

Watt

Question 18

When did the first nuclear power plant begin operation?

Answer 18

1954 A.D.

Question 19

The windmill was developed around which year?

Answer 19

950 A.D.

Question 20

Which property is not involved in thermal energy transfer?

Answer 20

Sound frequency

Question 21

The development of human civilization is dated around:

Answer 21

5000 B.C.

Question 22

What component is not part of solar energy conversion rate?

Answer 22

Fuel Tyoe

Question 23

What major energy-related invention was developed around 350 A.D.?

Answer 23

Water wheel

Question 24

Hydropower conversion rate depends on water flow and:

Answer 24

Falling Height

Question 25

Which direction does heat always flow

Answer 25

hot to cold

Question 26

What is the primary heat transfer mechanism in metals?

Answer 26

Conduction via free electrons

Question 27

What type of heat transfer occurs in boiling water causing fluid motion?

Answer 27

Natural convection

Question 28

Which heat transfer method becomes more significant at high temperatures?

Answer 28

Radiation

Question 29

Which of the following occurs fastest in turbulent flows?

Answer 29

Eddy diffusion

Question 30

What dimensionless number compares momentum and mass transfer?

Answer 30

Schmidt number

Question 31

Which type of energy transfer does lifting a book represent?

Answer 31

Mechanical work

Question 32

What energy conversion occurs when a battery powers a light bulb?

Answer 32

Electrical to thermal and light

Question 33

Which best describes work in a thermodynamic system?

Answer 33

Energy transfer due to force and displacement

Question 34

In a car engine, the movement of pistons is a result of:

Answer 34

Work by expanding gases

Question 35

What happens during an exothermic chemical reaction?

Answer 35

Energy is released

Question 36

Which of the following is true of an endothermic reaction?

Answer 36

Energy is absorbed from surroundings

Question 37

How does a catalyst speed up a chemical reaction?

Answer 37

Provides a lower activation energy pathway

Question 38

Which of the following reactions is exothermic?

Answer 38

Combustion

Question 39

What determines the rate of a chemical reaction, according to the Arrhenius equation?

Answer 39

Temperature

Question 40

Which part of a boundary layer mainly resists mass transfer?

Answer 40

Concentration boundary layer