Energy Resources and Energy Transfers

Question 1

kinetic energy =

Answer 1

1/2 x m x v^2

Question 2

kinetic energy rearranged for velocity

Answer 2

√(2E / m)

Question 3

kinetic energy rearranged for mass

Answer 3

2E / v^2

Question 4

how does doubling speed affect kinetic energy

Answer 4

increases kinetic energy by four
kinetic energy is proportional to the square of speed

Question 5

gravitational potential energy

Answer 5

mass x g x change in height

Question 6

energy stores

Answer 6

• kinetic
• chemical
• nuclear
• gravitational potential
• elastic potential
• thermal
• magnetic
• electrostatic

Question 7

energy transfers

Answer 7

• mechanical
• heating
• electrical
• radiation

Question 8

efficiency =

Answer 8

(useful energy / total energy) x 100

Question 9

convection

Answer 9

transfer of thermal energy, by moving particles in a gas or liquid due to differences of density

Question 10

conduction

Answer 10

transfer of heat from hot to cold through a solid material by collisions between vibrating particles and free electrons

Question 11

characteristics of good emitters

Answer 11

matte, black

Question 12

unit of kinetic energy

Answer 12

joules (J)

Question 13

unit of gravitational potential energy

Answer 13

joules (J)

Question 14

how to reduce energy transfers by convection in a system

Answer 14

insulation - insulated materials are bad conductors- reduces heat loss by conduction/convection

Question 15

reducing energy transfers by radiation

Answer 15

• double glazing
• cavity wall insulation

Question 16

radiation

Answer 16

energy that moves from one place to another in a form that can be described as waves or particles

Question 17

wind energy

Answer 17

• generate electricity by kinetic energy in the wind pushing the turbine.
• turbine is connected to a generator which converts the kinetic energy into electricity

Question 18

geothermal energy

Answer 18

• thermal energy in the ground heats up water into steam
• steam turns turbines with kinetic energy
• turbines connected to generator which converts the kinetic energy into electricity

Question 19

hydroelectricity

Answer 19

• water stored at a height is released to turn turbines in hydroelectric dams
• turbines connected to generators that convert kinetic energy into electricity

Question 20

solar energy

Answer 20

• thermal energy transferred is converted into electrical current
• produces electricity

Question 21

fossil fuels

Answer 21

• coal
• oil
• natural gases

Question 22

nuclear energy

Answer 22

• transferred into heat as it evapourates water
• steam turns turbines
• turbines connected to generators that converts kinetic energy into electricity

Question 23

advantages of wind as an energy source

Answer 23

• renewable energy source
• no costs for fuel (inexpensive to run)
• no harmful gases released into the atmosphere

Question 24

disadvantages of wind as an energy source

Answer 24

• eye-sore (ruins environment)
• loud
• energy reliant on the amount of wind

Question 25

advantages of hydroelectric power as an energy source

Answer 25

* renewable energy source * no fuel costs (inexpensive to run) * very reliable * can be switched on and off

Question 26

disadvantages of hydroelectric power as an energy source

Answer 26

* flooding of surrounding farmland * rotting vegetation under the dams releases methane

Question 27

advantages of geothermal electricity as an energy source

Answer 27

* renewable energy source * no fuel costs * no harmful gases released into the atmosphere

Question 28

disadvantages of geothermal electricity as an energy source

Answer 28

* lack of access for LICs

Question 29

advantages of solar power as an energy resource

Answer 29

* renewable energy source * no fuel costs * no harmful gases released into the atmosphere

Question 30

disadvantages of solar power as an energy resource

Answer 30

* expensive to build * reliant on the sun * uses a lot of space if not on buildings

Question 31

advantages of fossil fuels

Answer 31

* cost effective - cheap transportation * readily available in this time

Question 32

disadvantages of fossil fuels

Answer 32

* non renewable energy source * increasing costs * releases CO2 into the atmosphere (harmful)

Question 33

advantages of nuclear power as an energy source

Answer 33

* no harmful gases released into the atmosphere

Question 34

disadvantages of nuclear power as an energy source

Answer 34

* non renewable * can be extremely dangerous * high installation costs