Topic 3- Conservation of Energy Flashcards
(28 cards)
What is thermal conductivity?
Measure of how good something is as conducting heat.
Equation for thee change GPE?
Mass x gravitational feild strength (10) x Height (change)
MGH
Equation for KE?
1/2 Mass x Velocity^2
1/2MV^2
What is the conservation of energy?
-Energy cannot be created or destroyed
-only transfered from one fom to another
What happens to eenergy in a closeed system?
-No energy dissipates out
-Energy at the start is the same as energy at the end
How are Mechanical processes wasteful?
-Energy transfers to others and dissipates to the surroundings
How to reduce energy loss, for moving mechanics?
-Lubricant—> Less friction, usually a liquid
How to reduce thermal dissipation?
-Double glazing windows
-Cavity wall (air gap)
-Fit carpets
-Loft insulation
How does gaps between walls prevent heat loss?
-Gas is a poor heat conductor
-Harder for heat to dissipate
How to prevent heat loss through walls?
-Thicker walls
-Material that is poor heat conductor (concrete or plastic)
-Aluminium foil behind radiator
the more heat that a material conducts the higher the rate of transfer by conduction across the material
How does loft insulation work?
-contains fiberglass
-traps air
-Reduces convection (particle movement)
How do doublee glazed windows work?
-Trapes air between
-Air is poor conductor of heat
How does Aluminium foil behind radiator work?
-Reflects heat
Efficiency =
Useful / Total
How can efficiency be increased?
-Use waste energy/ recycle
-Reduce waste energy (Insulate/ lubricate)
Non renewable resources examples?
finite
-Fossil fuels
-Nuclear
-Natural gas/ coal/ oil
Renewable resources examples?
-Tidal
-Wave
-Hydroelectricity
-Wind
-Solar
-Bio fuel
-Geothermal
Geothermal?
Description:
-Magma heats rocks which heats water which forms steam to spin a turbinne
Advantages:
- Renewable
- No greenhouse gasses
- Reliable (day and night)
Disadvantages
- Location-specific (volcanic activity)
- High initial cost
- Environmental concerns
Tidal?
Description:
Tidal energy uses movement of ocean tides to turn turbines or generate electricity through a barrage system.
Advantages:
- Renewable
- No greenhouse gases
- Reliable (predictable tides)
Disadvantages:
- Location-specific
- High initial cost
- Environmental concerns (disruption to marine life)
Wind?
Description:
-Wind energy uses the movement of air to turn turbines, generating electricity from the kinetic energy of the wind.
Advantages:
- Renewable
- No greenhouse gases
- Low operating cost after installation
Disadvantages:
- Weather-dependent (wind must be strong enough)
- High initial cost
- Visual and noise pollution
Solar?
Description:
-Solar energy captures sunlight using photovoltaic cells to generate electricity or solar thermal systems to produce heat.
Advantages:
- Renewable
- No greenhouse gases
- Low operating cost after installation
Disadvantages:
- Weather-dependent (requires sunlight)
- High initial cost
- Requires a lot of space for large-scale systems
Biofuel?
Description:
-Biofuel is produced from organic materials like plants or waste, which are converted into liquid fuels (such as ethanol or biodiesel) to generate energy.
Advantages:
- Renewable
- Reduces waste (can be made from agricultural or industrial by-products)
- Can be used in existing engines and infrastructure
Disadvantages:
- Requires large amounts of land and water for crop production
- Can lead to deforestation or loss of biodiversity
- May produce greenhouse gases during production and use
Hydro?
Description:
-Hydroelectricity generates power by using the flow of water, typically from a dam, to turn turbines that produce electricity.
Advantages:
- Renewable
- Reliable (consistent water flow)
- Low greenhouse gas emissions
Disadvantages:
- Environmental impact (disrupts local ecosystems)
- High initial cost
- Location-specific (requires suitable river or water source)
