Energy And Energy Transfers

Question 1

What is chemical energy?

Answer 1

Stored in molecular bonds and released during chemical reactions

Question 2

What is kinetic energy?

Answer 2

Energy an object possesses due to motion

Question 3

What is thermal energy?

Answer 3

Total energy of particles in a substance due to their motion, increasing with temperature

Question 4

What is gravitational potential energy?

Answer 4

Stored when an object is lifted in a gravitational field

Question 5

What is elastic potential energy?

Answer 5

Stored when an object is stretched or compressed

Question 6

What are the pathways of energy transfer?

Answer 6

• Heating
• Mechanical
• Radiation
• Electrical

Question 7

How is energy measured?

Answer 7

In joules (J) and kilojoules (kJ)

Question 8

What is the relationship between kilojoules and joules?

Answer 8

1 kilojoule = 1,000 joules

Question 9

What is the energy requirement for simple tasks like standing and sitting?

Answer 9

6-7 kJ/minute

Question 10

What is the energy requirement for moderate tasks like walking slowly?

Answer 10

13-15 kJ/minute

Question 11

What is the energy requirement for cycling?

Answer 11

25 kJ/minute

Question 12

What is the energy requirement for running or swimming?

Answer 12

60-73 kJ/minute

Question 13

What happens when energy is dissipated?

Answer 13

It spreads out, often as heat, and becomes less available for useful work

Question 14

What is the law of conservation of energy?

Answer 14

Energy cannot be created or destroyed, only transferred or transformed

Question 15

How do energy and temperature differ?

Answer 15

• Energy: Powers actions and processes
• Temperature: Measures how hot or cold something is

Question 16

What is conduction?

Answer 16

Energy transfer through particle collisions in solids

Question 17

What is convection?

Answer 17

Energy transfer in fluids as warmer, less dense regions rise and cooler, denser regions sink

Question 18

What is radiation in the context of heat transfer?

Answer 18

Heat transfer via electromagnetic waves, which can occur in a vacuum

Question 19

What is infrared radiation?

Answer 19

A form of heat transfer that does not require a medium

Question 20

What are good emitters/absorbers of infrared radiation?

Answer 20

Black and dark-colored objects

Question 21

What are poor emitters/absorbers but good reflectors of infrared radiation?

Answer 21

White and shiny objects

Question 22

What defines renewable energy sources?

Answer 22

Sources that can be replenished at the same rate they are used

Question 23

What are some examples of renewable energy sources?

Answer 23

• Solar
• Wind
• Hydroelectric
• Geothermal

Question 24

What are the advantages of renewable energy?

Answer 24

• Sustainable
• Eco-friendly
• Can be installed on homes

Question 25

What are the disadvantages of renewable energy?

Answer 25

* Expensive setup * Often unreliable

Question 26

What defines non-renewable energy sources?

Answer 26

Sources that are finite and cannot be replenished at the rate of use

Question 27

What are some examples of non-renewable energy sources?

Answer 27

* Coal * Oil * Natural gas

Question 28

What are the advantages of non-renewable energy?

Answer 28

* Cheap * Reliable

Question 29

What are the disadvantages of non-renewable energy?

Answer 29

* Cannot be replenished at the rate of use * Environmentally harmful

Question 30

What are the steps in the electricity generation process?

Answer 30

* Chemical energy released through combustion * Heat converts water into steam * Steam spins turbines * Turbines drive generators

Question 31

What is the formula for work done?

Answer 31

Work Done = Force (N) × Distance (m)

Question 32

What is the formula for energy transferred?

Answer 32

Energy Transferred = Power (W) × Time (s)

Question 33

What is the principle of simple machines?

Answer 33

The force from the input is transferred to the output without creating or destroying energy