Revising for air resistance is such a drag
Alisa U Zemlji Chuda
art blog(derogatory)
Game of Thrones Daily

tannertan36
Mike Driver
almost home
Claire Keane

titsay
will byers stan first human second

JBB: An Artblog!
todays bird
RMH

shark vs the universe
Cosmic Funnies

ā
sheepfilms
Stranger Things
styofa doing anything
seen from United States
seen from United States
seen from United States
seen from United States
seen from United States

seen from United States

seen from United States
seen from United States
seen from United States
seen from South Korea
seen from United States

seen from Taiwan

seen from United States
seen from United States
seen from United States
seen from Canada
seen from France

seen from United Kingdom

seen from United States

seen from Ukraine
@gcsephysics
Revising for air resistance is such a drag

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
Free to watch ⢠No registration required ⢠HD streaming
Because I am absolutely useless at explaining distance-time and velocity-time graphs without physically (ha, get it: Physically! Hahahahahā never mind) having to make a video, hereās a video courtesy of BBC Bitesize to cover the main points discussed in previous posts⦠although I promise I will make my own post on the matter when I can be bothered to get my camera and pencils outā¦
That aside, this is a pretty good video, and isnāt very long (making it ideal for short bursts of revision), so give it a shot, and have a nice day! :D
Wave Power
as waves come into the shore, they provide an up and down motion which can be used to drive a generator
lots of wave powered turbines need to be located around the coast for it to generate a substantial amount of energy
there's no pollution, however they can be a hazard to boats and spoil the view
wave turbines are fairly unreliable as waves tend to die out when the wind drops
initial costs are high, but there are no fuel costs and minimal running costs
wave power is not good to provide energy on a large scale but can be very useful on small islands
Hydroelectric Power
hydroelectric powerĀ usually requires theĀ floodingĀ of aĀ valleyĀ by building a big dam
rainwaterĀ is caught and let out throughĀ turbines
there isĀ no pollutionĀ but there is aĀ big impactĀ on the theĀ environmentĀ due to theĀ floodingĀ of the valley -Ā rotting vegetationĀ releasesĀ CO2Ā andĀ methaneĀ and some species can lose theirĀ habitats
a big advantage is it can provide anĀ immediate responseĀ to anĀ increased demandĀ for electricity
alwaysĀ reliableĀ - except in times ofĀ drought
initial costsĀ are high but noĀ fuel's required andĀ running costsĀ areĀ low
Solar Power
solar cells generate electric currents directly from sunlight
they're often used in remote places such as the Australian OutbackĀ
they create no pollution, but use quite a bit of energy to manufacture in the first place
in sunny countries solar cells are a reliable source of energy, and can still be cost effective in cloudy countries - but only in the daytime
initial costs are high but after that energy is free and running costs are minimal
usually not practical or too expensive to connect them to the national grid - they're better used on a small scale

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
Free to watch ⢠No registration required ⢠HD streaming
Wind Power
wind turbines are located in exposed places like on moors or round coasts
each turbine has it's own generator inside it so electricity is generated directly from the wind turning the blades, which turn the generator
there's no pollution (other than manufacturing)
some people say they spoil the view
1500 wind turbines are required to generate the same amount of energy as one coal-fired power station, and these take up a lot of space and change the scenery
they can be very noisy, which is annoying for nearby residents
wind turbines are dependent on the weather- when there's no wind, no power is generated
the initial costs are quite high, but there are no fuel costs and minimal running costs
they create no permanent damage to the environment
Power Stations
the fossil fuel is burned to convert stored chemical energy into heat (thermal energy)
the thermal energy is then used to heat water to produce steam
the steam turns a turbine, converting heat into kinetic energy
the turbine is connected to a generator, which transfers kinetic energy into electrical energy
voltage is increased by a step-up transformer for efficient transmission, then the electricity is distributed to homes via the national grid
Energy Sources
non renewable energy resources will run out one day and they all do damage to the environmentĀ but currently provide most of our electricity
coal
oil
natural gas
nuclear fuels (uranium and plutonium)
renewable energyĀ resources will never run out, most of them still do damage the environment, but in less nasty ways than non-renewable, however they don't provide a lot of energy and are often unreliable because they depend on the weather
wind
waves
tides
hydroelectric
solar
geothermal
food
biofuels
The Cost of Electricity
the amount of energy transferred by an appliance depends on its power and the amount of time the appliance is switched on
power is usually measured in watts (W) or kilowatts (kW)
energy is usually measured in joules (J) but the standard units of electrical energy are kilowatt-hours
a kilowatt-hour is the amount of electrical energy used by a 1 kW appliance left on for 1 hour
ENERGY = POWER x TIME
No. of UNITS (kWh) used = POWER (kW) x TIME (hours)
and to find the cost:
COST = No. of UNITS (kWh) x PRICE per UNIT
Heat radiation.
*puts finger on butt*
TSSSSS
More notes

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
Free to watch ⢠No registration required ⢠HD streaming
Sankey Diagrams
sankey diagrams, or energy transformation diagrams, are a visual representation to how much energy put into a machine is being used usefully and how much is being wasted
the thicker the arrow, the more energy it represents
you can use these to calculate the efficiency
Efficiency of Machines
a machine is a device that transforms energy from one form to another
some of the input energy is always lost or wasted as heat
the less energy that's wasted, the more efficient the device is
the efficiency of any device can be found using:
the efficiency can be writtenĀ as a decimal (0.33) or a percentage (33%) by multiplying by 100
no device is 100% efficient and the wasted energy is usually spread out as heat (except heaters)
ENERGY can be TRANSFERRED usefully from one form to another, STORED or DISSIPATED - but it can never be CREATED or DESTROYED
conservation of energy principle
electrical energy - whenever a current flows
light energy - from the sun, light bulbs etc.
sound energy - from loudspeakers or anything noisy
kinetic energy - anything that's moving has it
nuclear energy - released from nuclear reactions
thermal/heat energy - flows from hot objects to cooler ones
gravitational potential energy - in stretched springs, elastic, rubber bands etc.
chemical energy - possessed by foods, fuels, batteries etc.
potential and chemical energy are forms of stored energy - it is waiting to be turned into another form
Specific Heat Capacity
specific heat capacityĀ is a measure of how much energy different materials canĀ store
the specific heat capacity of a substance is the amount of energy needed to change the temperature of 1 kg of the substance by 1°C
you can work out the specific heat capacity of a substance using this formula:
E = m x c x Ć
E is energy transferred (J) m is mass (kg) c is specific heat capacity à is temperature change (°c)
water has a specific heat capacity of 4200 J/kg °c
materials used in heaters haveĀ high specific heat capacitiesĀ so they can storeĀ large amountsĀ of heat energy

Anya is live and ready to show you everything. Watch her strip, dance, and perform exclusive shows just for you. Interact in real-time and make your fantasies come true.
Free to watch ⢠No registration required ⢠HD streaming
U-Values
a u-value is a measure of heat loss in a building element
the higher the u-value, the faster heat transfers through the material
the better the insulator, the lower the u-value
Energy Efficiency in the Home
lots of heat energy can escape from a badly insulated home
there are many things you can do to a building to reduce this heat loss
the most effective methods of insulation are ones which give the homeowner the biggest annual saving
cavity wall insulationĀ is foam squirted into the gap between bricks and this reduces convection and radiation across the gap
loft insulationĀ is a thick layer of fibreglass wool laid out across the whole loft floor and this reduces conduction and radiation into the roof space from the ceiling
draught proofing is strips of foam and plastic around doors and windows to stop draughts of cold air - reducing heat loss due to convection
hot water tank jacket reduces conduction and radiation
thick curtains are big bits of cloth over windows to reduce heat loss by conduction and radiation