P1 Flashcards
What is kinetic energy?
The energy due to motion
What is elastic potential energy?
The energy stored in a stretched object
What is specific heat capacity?
The amount of energy required to raise 1kg of a substance by 1 degree
What is the conservation of energy?
Energy cannot be created or destroyed, only transferred
What is a system?
Object or group of objects
What is gravitational potential energy?
Energy stored in an object due to its position in a gravitational field
What is thermal energy?
Energy due to beat
What is power?
The rate of energy transfer
What is wasted energy?
Energy transferred into a form that is not the desired outcome
What are the different thermal energy transfers?
Conduction and convection
What is thermal conductivity?
The measure of how well a material conducts energy when it is heated
Why are metals good at conduction?
Metals have delocalised electrons
What is efficiency?
A measure of how much of the energy we put in ends up in useful energy stores
What are the four ways of energy transfer and how do they work?
Mechanical work- involves a force moving an object
Electrical work- involves an electrical current flowing
Heating- due to a temperature difference
Radiation- energy transferred as a wave (e.g. light)
What are the 7 energy stores?
Gravitational potential
Elastic potential
Thermal
Electromagnetic
Nuclear
Chemical
Kinetic
What are the non-renewable resources?
Nuclear
Oil
Gas
Coal
What is bad about nuclear power?
They do not release carbon dioxide, but produce radioactive waste which must be carefully contained
Why are fossil fuels bad?
Burning fossil fuels results in emission of greenhouse gases which contribute to global warming
What is renewable energy?
Renewable sources of energy that never run out and they tend to be less damaging to the environment
What are examples of renewable energy?
Geothermal
Biofuel
Solar
Tidal
Wind
Hydroelectric
Wave
What are the advantages and disadvantages of fossil fuels?
ADVANTAGES- cheap, quick, produces a lot of energy, reliable, the infrastructure is already in places
DISADVANTAGES- factor to global warming, finite resource, bad for environment, causes acid rain, the gases produced are bad for plants and animals
What are the advantages and disadvantages of nuclear fuel?
ADVANTAGES- they give people work, don’t emit CO2, lot more energy than coal, reliable
DISADVANTAGES- dangerous, radiation, significant if something goes wrong, life threatening, non renewable, waste is stored for centuries, very expensive due to safety regulations
How do you calculate the specific heat capacity of a material?
Use the equation: change in thermal energy = mass × specific heat capacity × temperature change.
What is the formula to calculate energy transferred by a heater?
Energy transferred = current x voltage x time.
Why is the experimental result for specific heat capacity usually too high?
The result is usually too high due to thermal energy dissipated to surroundings.
What is the first step in calculating specific heat capacity?
Work out the energy transferred by the heater.
What equipment is mentioned in the context of measuring temperature?
Thermometer.
What are fossil fuels used for?
Burnt to make steam to drive a turbine
What is the process for nuclear energy?
Uranium and Plutonium make steam to drive a turbine
How is biofuel utilized?
Burn fuel from living materials to make steam to drive a turbine
What drives a wind turbine?
Wind drives a turbine
How does hydroelectric power work?
Water goes through a dam to drive a turbine
What drives a tidal turbine?
Falling tide drives a turbine
How is solar energy converted?
Light energy converted to electricity
What produces steam in geothermal energy?
Volcanic rocks produce steam to drive a turbine
What is wave energy converted to?
Wave kinetic energy converted to electricity
What are the characteristics of reliable energy sources?
Cheap to buy, can respond to change in demand (gas), powerful
What is a benefit of renewable energy?
No CO2, contributing to global warming
What is a feature of renewable energy in winter?
Works well in winter
What can renewable energy do with energy storage?
Can store energy from other stations
What are the drawbacks of non-renewable energy?
Produce CO2 causing global warming
What does coal produce that causes acid rain?
Coal produces SO2, causing acid rain
What are the concerns with nuclear energy?
Nuclear waste/accidents, cannot respond to changes in demand
What are the environmental impacts of biofuel?
Wastes farmland, deforestation to grow crops
What are some characteristics of unreliable energy sources?
Relatively low power, expensive to build, visual pollution, kills birds
What are the issues with tidal energy?
Flood land and destroys habitats, few suitable locations
What is a drawback of solar energy?
Works at wrong times e.g. day/summer, low power
What is a limitation of geothermal energy?
Needs volcanic activity, unreliable, low power
How can you reduce unwanted energy transfer in a machine with moving parts?
Use a lubricant to reduce friction
How can you reduce unwanted energy transfer in a heated building in winter?
Use increased thermal insulation
