P1-Energy Flashcards
Name the different energy stores (8)
- Chemical
- Kinetic
- Gravitational Potential (GPE)
- Thermal energy (Internal)
- Elastic Potential (EPE)
- Magnetic
- Nuclear
- Electrostatic
What is a magnetic energy store?
Give 3 examples
The energy stored when repelling poles have been pushed closer together or when attracting poles have been pulled further apart
Fridge magnets, compasses, maglev trains
What is a thermal (internal) energy store?
Give 3 examples
The total kinetic energy of the particles in an object
Human bodies, hot coffees, stoves or hobs,
-anything above absolute 0
What is a chemical energy store?
Give 3 examples
The energy stored in chemical bonds
Foods, Muscles, Batteries
What is a kinetic energy store?
Give 3 examples
The energy of a moving object
Cars, Comets, Runners
What is an electrostatic energy store?
Give 2 examples
The energy stored when repelling charges have been moved closer together or when attracting charges have been pulled further apart
Thunderclouds, Van De Graaff generators
What an elastic potential energy (EPE) store?
Give 3 examples
The energy stored when an object is stretched or squashed
Stretched elastic bands, Inflated Balloons, Compressed springs
What is a gravitational potential energy (GPE) store?
Give 3 examples
The energy of an object at height
Aeroplanes, Kites, Mug on a table
What is a nuclear energy store?
Give 2 examples
The energy stored in the nucleus of an atom
Radioactive elements, Nuclear reactors
List the 4 different ways energy can be transferred
- Mechanical work
- Electrical work
- Heating
- Radiation
Describe mechanical work
A force moving an object through a distance
Describe electrical work
A charge moving due to a potential difference-energy is transferred in a circuit.
Describe heating
An increase in thermal energy caused electrically or by chemical reaction
Describe radiation
Energy transferred as a wave
What are the 2 energy flow diagrams?
- Transfer diagrams
- Sankey diagrams
What energy flow diagram shows how much energy is transferred to each source?
Sankey diagram
What is the principle of conservation of energy?
Energy cannot be created or destroyed
What are the two energy systems?
Open and closed systems
What is a closed system?
An system in which no energy transfers take place out side of or into the energy stores of the system
What is energy transferred also called?
Work done
What is the equation linking work done, force and distance
work done = force applied x distance moved
W=Fd
What is the unit of measurement used for work done?
joules
J
What is the unit of measurement used for force?
newtons
N
What is the unit of measurement used for distance?
metres
m
What is the formula for gravitational potential energy (GPE)?
change in GPE = mass x gravitational field strength x change in height
ΔEₚ = mgΔh
What is the unit of measurement used for mass?
kilograms
kg
What is the formula for kinetic energy?
kinetic energy = 1/2 x mass x velocity²
Eₖ = 1/2 mv²
What is the unit of measurement used for velocity?
metres per second
m/s
What is the formula for elastic potential energy (EPE) also called Hooke’s law?
elastic potential energy = 1/2 x spring constant x extension²
Eₑ = 1/2ke²
What are the units of measurement used for the spring constant?
newtons per metre
N/m
What are the 2 energy types?
Useful energy
Wasted energy
What happens to wasted energy?
It dissiapates
What is the formula for % efficacy of energy?
%efficiency=(useful energy/total energy) x 100
What is the formula for power?
power = energy transferred/time
P = E/t
What is the unit of measurement used for power?
watts
W
What is the formula for % efficacy of power?
%efficiency=(useful power out /total power in) x 100
What affects the energy transfer/second through a layer of insulating material?
- The temperature difference
- The material thickness
- The material thermal conductivity
What radiation do all objects emit?
Infrared radiation
What part of the visible spectrum is infrared radiation?
Just beyond the red part
What colour absorbs and emits infrared radiation the best?
Black
In what circumstance does the temperature of an object increase due to radiation?
When it absorb more radiation than it emits
What is the definition of specific heat capacity?
The amount of energy it takes to raise the temperature of 1kg of a substance by 1°C
(J/kg/°C)
What is the formula for thermal energy transferred involving specific heat capacity?
energy transferred = mass x specific heat capacity x temperature change
ΔE=mcΔθ
What is the unit of measurement used for
temperature?
degrees Celsius
°C
List Renewable energy sources
- Wind energy
- Wave energy
- Hydroelectric energy
- Tidal energy
- Solar energy
- Geothermal energy
- Biomass
List Non-renewable energy sources
- Nuclear
- Fossil fuels
List advantages of Nuclear power
No greenhouse gases produced
High amount of energy/kg of uranium
Cheap
List disadvantages of Nuclear power
Radioactive waste has to be stored safely for centuries
If something goes wrong there are catastrophic consequences
List advantages of Renewable energy sources
- They will never run out
- They don’t produce greenhouse gases
- They don’t create radioactive waste products
- They can be used where connection to the national grid is uneconomical
List disadvantages of Renewable energy sources
Not currently able to keep up with energy demands
Wind turbines create sound and visual pollution
Hydroelectric schemes and Tidal barrages affect wildlife
Solar cells take up a large land area
Some renewable energy sources aren’t reliable-can’t produce energy at some times
