P1-Energy Flashcards
What are the four ways which energy is transferred
– Mechanically, electrically, heating, radiation
What is Power
The rate of doing work
What is the conservation of energy principal
Energy can be transferred usefully, stored or dissipated, but can never be created or destroyed
How do you reduce unwonted energy transfers
Lubrication, insolation
How do you lubrication reduce friction forces
Lubrication is used to reduce the friction between objects services when they move – it prevents the energy being dissipated
How does heating occur
By conduction or convection
What is conduction
The transfer of energy when the particles vibrate and collide – transferring between Kinetic energy stores
What is convection
When the energy particles move from the hotter to cooler regions
What are the ways of preventing energy loss – insolation
Having thick walls are made from material with low thermal conductivity
– Thermal insulation
What are the four methods of the thermal insolation
– Cavity walls
– loft insulation
– double glaze windows
– draught excluders
What are cavity walls and how do they reduce energy loss
Some houses have cavity walls which are made up of inner and outer wall with an air gap in the middle. But I got reduces the amount of energy transferred by conduction through the walls
– cavity wall insulation is where the cavity wall gap is filled with foam, which can also reduce energy transfer by convection
What is Loft installation how to produce energy lost
Love desolation reduces convection current’s (a cycle where air particles are constantly being heated, rising, calling and then sinking)
What are double glaze windows and how did they prevent energy transfer
Double glaze windows work in the same way as cavity walls – I have an air gap in the middle between two sheets of glass to prevent energy transfer by conduction
How do draught excluder’s work
Draft excluder is around doors and windows reduce energy transfer by convection
How do you increase the efficiancy of an intended energy transfer
By insulating objects, lubricating them or making them more streamlined
What is a renewable energy source
A resource that is being hall can be replenished as it is used
What are the nonrenewable energy sources
Coal, oil, gas
What are the renewable energy resources
The sun, wind, water waves, hydro electricity, Abaya fuel, tides, geothermal
What are the uses of energy resources
Transport or heating
Heating e.g. radiators,: fireplaces, electric heaters
Transport e.g. petrol diesel used from oil,Coal in steam trains
Positives and Negatives of wind power
+ No pollution, there are no fuel and minimal running costs,
– Wind isn’t always available
– they can spoil the view
– they are very noisy
– The initial costs are quite high
Advantages and disadvantages of solar cells
Advantages: usually in remote places, no pollution, very reliable,
Disadvantages: not great in cloudy countries, initial costs are high, can’t increase output when his extra demand
Advantages and disadvantages of geothermal power
Advantages: it produces a lot of free energy, does Very little damage to the environment,
Disadvantages: There is not many suitable locations for power plants, the cost of power plants is often high
Branches and disadvantages of hydroelectric power
Advantages: there are no problems with Liability, no pollution
Disadvantages: loss of habitat, costs,
Advantages and disadvantages of wave power
Advantages: no pollution,
Disadvantages: disturbs habitats, spoils you, hazard to boats, fairly unreliable, initial costs are high
Tidal barrages Advantages and disadvantages
Advantages: reliable
Disadvantages: habitat, high costs, prevents access to boats
What are the environmental problems from fuels
Greenhouse effect, sulphur Darkside – acid rain, landscape, oil spillages,
What is the specific heat capacity
The energy required to increase the temperature of 1KG of a substance by 1°
What’s the equation for specific heat capacity
Mass X specific heat Capacity X Change in temperature
