FWE: ENERGY

What is energy?

What is energy?

Energy is the capacity to do work

What is the SI unit for energy?

Joule (J)

What kind of potential energy is there?

• Chemical Potential Energy (food and fuel)

• Gravitational Potential Energy (position or location)

  • Depends on mass and height of object

• Elastic Potential Energy (stretched or compressed)

What is kinetic energy and what affects it

Kinetic Energy is motion.

Depends on speed and mass of object

What can energy be transferred as

• thermal energy (heat but cannot write as heat energy)

• light energy

• sound energy

• electrical energy

how is thermal energy transferred

Flows from a region of higher temperature to a region of lower temperature

PRINCIPLE OF CONSERVATION OF ENERGY:

Energy cannot be created or destroyed, but can be transferred from one object to another, or converted from one form to another (AKA total amount of energy does not change)

SWINGG: what energy is there at highest and lowest points

Highest Point:

• Max GPE

• No KE

Lowest Point: (assuming friction and air resistance is negligible)

• No GPE

• Max KE

SWINGG: what happens if there is air resistance and friction and why?

some energy is transferred to the surroundings as heat and sound because the object overcomes air resistance and friction in the hinges

ENERGY RESOURCES:

1. Fossil fuels

2. Solar energy

3. Wind energy

4. Hydroelectric energy

5. Geothermal energy

6. Biofuels

7. Nuclear energy

Fossil fuels: energy flow in Power station

Chemical potential energy (fossil fuel) → thermal energy (water) → kinetic energy (steam) → kinetic energy (turbine) → electrical energy (generator)

Impact of fossil fuels on environ

• Release air pollutants and greenhouse gases

• Global warming + climate change

Solar energy: energy flow in solar panels

light energy (the sun) → electrical energy (solar cell)

Impact of solar energy on environ

Toxic waste generated during production and disposal of solar panels (must take enough care of this)

Wind energy: energy flow in wind turbines

kinetic energy (wind) → kinetic energy (wind turbine) → electrical energy (generator)

Impact of wind energy on environ

• Alot of land cleared 

• Results in loss of natural habitats

• Results in loss of wildlife

• Birds may die when collided with the blades 

• Noise pollution

Hydroelectric energy: energy flow in hydroelectric dam

gravitational potential energy (water stored behind a dam) → kinetic energy (water) → kinetic energy (turbine) → electrical energy (generator)

Impact of hydroelectric energy on environ

• Flooding

• Kills plants 

• Force animals to move to other areas

• Fishing ppl may have to relocated further inland (not be able to fish anymore)

Geothermal energy: energy flow in geothermal power plant

thermal energy (Earth’s core) → kinetic energy (steam) → kinetic energy (turbine) → electrical energy (generator)

Impact of geothermal energy on environ

• Alot of land loss

• Loss of habitat

• Loss of wildlife

• Toxic elements buried underground are drawn out

Biofuels: uses and what its made from

• Used as fuel (e.g. cars)

• Made from plants and then go into the factory, mixed with other fuels, become biofuel

Biofuel: energy flow for vehicle

Chemical potential energy (biofuel) → thermal energy (air in engine)  → kinetic energy (vehicle)

Impact of biofuel on environ

• Release air pollutants 

• Major threat to supply of food globally

• Destruction of forest for farming of biomass

Nuclear energy: energy flow in nuclear plant

nuclear energy (atoms) → thermal energy (water) → kinetic energy (turbine) → electrical energy (generator)

Impact of nuclear energy on environ

• Risk to health and safety of communities living near plant cuz of the nuclear waste

• Waste can contaminate groundwater and surface water sources