Card #1/24. Describe how thermal energy is passed on in terms of ions Using these ideas explain how a convection current occurs

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1 Card #1/24 Card #2/24 Topic: Conduction Topic: Convection In what state of matter does conduction occur? In what states of matter does convection occur? Explain why it needs to be in this state? Define the term density Describe how thermal energy is passed on in terms of ions Using these ideas explain how a convection current occurs Topic: Radiation Card #3/24 Card #4/24 Topic: evaporation and condensation What is unique about radiation as a means of transferring thermal energy? Where can you see evaporation occurring? What coloured surfaces are good at absorbing and emitting thermal radiation? What coloured surfaces are good at reflecting thermal radiation? Where can you see condensation occurring? State the conditions which are best for evaporation and thus cooling to occur

2 Card #2/24 Card #1/24 Fluids expand when they are heated. This is because the particles in fluids move faster when they are heated than they do when they are cold. As a result, the particles take up a greater volume. The fluid in hot areas is less dense than the liquid or gas in cold areas, so it rises into the cold areas. The denser cold liquid or gas falls into the warm areas. In this way, convection currents that transfer heat from place to place are set up. Conduction is how heat energy is transferred through solids when they are heated. Heat energy can also be passed from one solid to another by conduction. Conductors are materials which transfer energy more easily. Insulators are materials which don t transfer heat as well for example, Glass and plastics. As the conductor is heated the atoms gain more energy and vibrate more. This causes them to collide with other atoms transferring the heat energy. Card #4/24 Card #3/24 Evaporation The particles in a liquid have different energies. Some will have enough energy to escape from the liquid and become a gas. When they leave the liquid we say they have evaporated. The warmer the liquid is the faster this happens. Condensation The particles in a gas have different energies. Some may not have enough energy to remain as separate particles, particularly if the gas is cooled down. They come close together and bonds form between them. Condensation and evaporation occur quickly when; -It is warm -Big surface area -It is windy All objects emit (give out) and absorb (take in) infra red radiation. The hotter an object is the more infra red radiation it gives out. Absorption, emission and reflection Black (Dark, matt) surfaces are both good absorbers and good emitters of infra red radiation. Light shiny surfaces are both poor absorbers and poor emitters of infra red radiation. Light, Shiny Surfaces are good reflectors of infra red radiation

3 Card #5/24 Card #6/24 Topic: Insulating buildings Topic: Energy transfers Define what a U value is Draw a Sankey diagram to show the energy transfer in a TV. Is it better for a building to be built from materials with high or low u values? Describe how energy is conserved. Card #7/24 Card #8/24 Topic: Efficiency Topic: Energy transfer calculation What would the efficiency of a light bulb be if 100J of electricity was supplied and 55J was converted to heat and 45J converted to light? How much energy is transferred by a 10kW shower if it is used for 30 minutes per day for a week? What would the efficiency of a light bulb be if 500J of electricity was supplied and 370J was converted to heat and 130J converted to light? How much energy is transferred if a

4 Card #6/24 Card #5/24 U-Values U values measure how effective a material is an insulator. The lower a U-Value is the better the insulator it is. Card #8/24 Card #7/24 Efficiency Efficiency is a measure of how much wasted energy is

5 Card #9/24 Card #10/24 Topic: Generating electricity from fossil fuels Topic: Generating electricity from nuclear fuel What is the sequence for generating electricity in a fossil fuel power station? What process happens in a nuclear reactor? What are the advantages and disadvantages of nuclear power? How does a power station effect the environment? Topic: Generating electricity from renewable resources How do we get electricity from a wind turbine? Card #11/24 Card #12/24 Topic: Generating electricity from renewable resources How do we get electricity from a geothermal power station? How do we get electricity from a hydroelectric dam and why is it useful for sudden surges in demand? How do we get electricity from wave power? How do we get electricity from a solar panel?

6 Card #10/24 Card #9/24 Uranium and plutonium which release energy from nuclear fission and are used to heat water. The steam produced drives a turbine that is coupled to an electrical generator. Advantages Nuclear fuels do not produce carbon dioxide or sulfur dioxide. 1 kg of nuclear fuel produces millions of times more energy than 1 kg of coal. Disadvantages Nuclear fuels are non-renewable energy resources. If there is an accident, large amounts of radioactive material could be released into the environment Nuclear waste remains radioactive and is hazardous to health for thousands of years. In most power stations a fossil fuel (coal, oil or gas) is burnt to heat water. The steam produced drives a turbine that is coupled to an electrical generator. Advantages of using fossil fuels cheap, easy to obtain and much of our infrastructure is designed to run using fossil fuels. Disadvantages of using fossil fuels Fossil fuels are non-renewable energy resources, they contribute to acid rain and Increases global warming. Card #12/24 Card #11/24 Solar cells use the suns light energy directly to produce electrical energy. In some volcanic areas hot water and steam rise to the surface. This steam can be tapped and used to drive turbines. This is known as geothermal energy. Wave power Generators. When a wave hits the generator it forces the air in the tube to rise which in turn forces the air through a turbine, this makes the turbine spin and if connected to a generator generates electricity. Hydro Electric power stations use falling water to turn turbines, which are connected to a generator that generates electricity.. We can control when realise the water meaning electricity is generated only when it is needed. Wind causes the turbine blades to spin, which are connected to a generator that generates electricity. The faster the blades spin, the more electricity is produced. to

7 Card #13/24 Card #14/24 Topic: National grid Topic: Waves and wave speed equation What is the national grid and which components make it up? What are the units of wavelength, frequency and speed? Why is it important to transfer the electricity at a high voltage? If a wave had a wavelength of 45m and a frequency of 25Hx what would the speed be? If a wave was travelling at 300,000km/s with a wavelength of 45Hz what would the wavelength be? Topic: Electromagnetic spectrum Card #15/24 Card #16/24 Topic: Sound waves What type of wave are waves from the electromagnetic spectrum? What are the different parts to the electromagnetic spectrum? Which parts can be used for communication? What type of waves are sound waves? How would an oscilloscope trace alter for a higher pitched sound? How would an oscilloscope trace alter for a louder sound?

8 Card #14/24 Card #13/24 The National Grid Electricity is distributed from power stations to consumers along the National Grid. The national grid is made up of; - Wires and pylons - Step Up transformers - Step down transformers Card #16/24 Card #15/24 Sound waves are longitudinal waves and cause vibrations in a medium, which are detected as sounds. the greater the amplitude, the louder the sound the greater the frequency, the Electromagnetic waves are transverse waves which all travel at the same speed through a vacuum (the speed of light) The low energy end of the electromagnetic spectrum are used for communications. Radio Television and radio signals Microwave Mobile phone and satellite television signals Infra Red Remote controls

9 Card #17/24 Card #18/24 Topic: Reflection Topic: Refraction Where is the normal line in a ray diagram? Describe refraction What is the relationship between angle of incidence and angle of refraction? What causes refraction to occur? What is a virtual image? Card #19/24 Card #20/24 Topic: Diffraction Topic: Doppler effect and Red shift What is diffraction? What is the Doppler effect? When can you get a wave to diffract the most? What are spectral lines? How does the position of spectral lines differ if the stars are moving away faster?

10 Card #18/24 Card #17/24 Card #20/24 Card #19/24 Doppler effect If a wave source is moving relative to an observer there will be a change in the wavelength. If the wave source is moving towards you the wave gets bunched up. If it is moving away from you the wave gets spread out the wavelength is longer. Red shift - The same happens in lights rays coming form stars that are moving away from us. The further away the bigger the red shift. Spectral lines for our sun Diffraction is when a wave spreads out after passing through a gap. Significant diffraction only occurs when the size of gap the wave is passing through is of a similar magnitude to the wavelength. Spectral lines for distant star.

11 Card #21/24 Card #22/24 Topic: specific heat capacity Topic: What is specific heat capacity? How much energy would it take to heat 10kg of water by 10 degrees celcius if the specific heat capacity was 4181 J/kg o C? What would the mass of an aluminium bar be if it had a specific heat capacity of 900 J/kg o C and 1000Kj has raised its temperature by 7 o C? Card #23/24 Card #24/24 Topic: Topic:

12 Science Revision C1 Card #22/24 Card #21/24 Specific heat capacity The specific heat Capacity of a substance is the amount of energy required to change the temperature of the substance by one degree Celsius. Science Revision C1 Card #24/24 Science Revision C1 Card #23/24