Energy

Question 1

What is energy

Answer 1

Energy is defined as the ability to do work

Question 2

What units are used to measure energy

Answer 2

Joules

Question 3

What is work done

Answer 3

Work is done when a force acts on an object and causes it to move through a distance in the direction of the force

Question 4

What is the equation for work done

Answer 4

Work done = force * distance moved

Question 5

How much work was done when a man lifted a 75kg bar 2 meters above the ground

Answer 5

Work done = (75*10) * 2
= 1500 J

Question 6

How is work done related to energy transferred

Answer 6

Work done = Energy transferred

Question 7

What are the eight energy stores

Answer 7

Gravitational Energy
Kinetic Energy
Elastic Energy
Thermal Energy
Chemical Energy
Magnetic Energy
Electrostatic Energy
Nuclear Energy

Question 8

How do objects gain Gravitational Potential Energy

Answer 8

Objects gain G.P.E by moving higher

Question 9

What is the equation for GPE

Answer 9

GPE (J) = mass (kg) * gravitational field strength * height

Question 10

Name 2 objects that store G.P.E

Answer 10

An object on top of a shelf, an airplane flying

Question 11

How do objects that store Kinetic Energy have the ability to do work

Answer 11

Objects that store kinetic energy have the ability to do work by changing their speed

Question 12

What is the equation for kinetic energy

Answer 12

Kinetic energy = mass * speed^2 / 2

Question 13

Name 2 objects that store K.E

Answer 13

A person running, A moving bike

Question 14

How do objects that store elastic energy have the ability to do work

Answer 14

Objects that store elastic energy have the ability to do work by changing their shape

Question 15

Name 2 objects that store elastic energy

Answer 15

A stretched bow, springs

Question 16

Where is chemical energy stored

Answer 16

Chemical energy is stored in the bonds between the particles of the material

Question 17

How do objects that store thermal energy have the ability to do work

Answer 17

Objects that store thermal energy have the ability to do work by changing their temperature

Question 18

What is the difference between heat and thermal energy

Answer 18

Thermal energy is the energy stored in an object due to the movement of the particles it is made of, while heat is the amount of thermal energy transferred from a hot to a cold body

Question 19

What is the principle of conservation of energy

Answer 19

Energy cannot be created or destroyed, it can only be transferred from one store to another

Question 20

What are four ways of energy transfer

Answer 20

Mechanically
Electrically
By heating
By radiation

Question 21

How is energy transferred mechanically

Answer 21

Energy is transferred mechanically when a force acts through a distance doing work

Question 22

How is energy transferred electrically

Answer 22

Energy is transferred electrically through the flow of electric charge in an electric circuit

Question 23

How is energy transferred by heating

Answer 23

Energy is transferred by heating from a hotter object to a colder one, resulting in the difference in temperature between them to decrease

Question 24

How is energy transferred by radiation

Answer 24

Energy is transferred by waves through materials and from place to place

Question 25

What is the equation for efficiency

Answer 25

efficiency = useful energy output / total energy input

Question 26

Where is wasted energy transferred to

Answer 26

Wasted energy is transferred to the surroundings as thermal energy mechanically (by friction) or through heating (temperature difference)

Question 27

What is power

Answer 27

Power is the rate of doing work

Question 28

What is the equation for power

Answer 28

Power = Work done / time taken

Question 29

What are the units of power

Answer 29

Watts

Question 30

What are non-renewable energy sources

Answer 30

Non-renewable energy sources are those who cannot be replaced once they are used up

Question 31

Give examples of fossil fuels

Answer 31

Coal Oil Natural Gas

Question 32

What are the advantages of fossil fuels

Answer 32

More reliable as they are not weather dependent High energy density

Question 33

What are the disadvantages of fossil fuels

Answer 33

They will run out Produce CO2 when burnt which causes global warming Produce sulfur dioxide when burnt which causes acid rain

Question 34

What are the advantages of nuclear fuels

Answer 34

No atmospheric pollution Not weather dependent High energy density

Question 35

What are the disadvantages of nuclear fuels

Answer 35

Will run out Difficult to dispose radioactive waste Danger of nuclear accidents High initial set up costs

Question 36

What are renewable energy sources

Answer 36

Renewable energy sources are those that can be used repeatedly without running out

Question 37

What are the advantages and disadvantages of renewable energy sources

Answer 37

Advantages: They will not run out They do not produce greenhouse gases The fuel is usually free Disadvantages: Power stations have a high initial set up cost

Question 38

What are some types of renewable energy sources

Answer 38

Solar energy Tidal energy Geothermal energy Hydroelectric energy Wind energy Biomass

Question 39

What are the advantages and disadvantages of solar energy

Answer 39

Advantages: Can be put on existing buildings Disadvantages: Can be used only when sunny Require a large area of panels Visual pollution

Question 40

What are the advantages and disadvantages of tidal energy

Answer 40

Advantages: Disadvantages: Large areas of water must be enclosed, altering wildlife habitats

Question 41

What are the advantages and disadvantages of geothermal energy

Answer 41

Advantages: Consistent power output Doesn't take up a lot of space Disadvantages: Can only be built in areas of volcanic activity

Question 42

What are the advantages and disadvantages of hydroelectric energy

Answer 42

Advantages: Not weather dependent Disadvantages: Large dams have to be built, destroying natural habitats It can only be used in wet regions

Question 43

What are the advantages and disadvantages of wind energy

Answer 43

Advantages: Reduced running costs Disadvantages: Noisy and unsightly Only run when windy Many generators are needed for sufficient energy

Question 44

How is electricity produced

Answer 44

Stored energy (coal, oil, gas) is used to heat water and convert it into steam. This steam is used to drive and rotate the turbines that in turn spin a generator that produces electricity

Question 45

What is conduction

Answer 45

Thermal conduction is the transfer of thermal energy through one or more substances that are in contact by the vibrations of the atoms within the substance

Question 46

How is thermal energy transferred by conduction

Answer 46

When a part of a solid is heated, its particles start vibrating faster and collide with the particles of the colder part which are moving slower. When colliding, the faster moving particles transfer some of their kinetic energy to the slower moving ones, which gain kinetic energy and pass it on. This process is repeated causing temperature to increase

Question 47

NOT ENTIRE CHAPTER

Answer 47

good luck bro