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Which objects are good absorbers of IR radiation? Describe the process of heat transfer by conduction in 3 steps Describe the process of heat transfer.

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Presentation on theme: "Which objects are good absorbers of IR radiation? Describe the process of heat transfer by conduction in 3 steps Describe the process of heat transfer."— Presentation transcript:

1 Which objects are good absorbers of IR radiation? Describe the process of heat transfer by conduction in 3 steps Describe the process of heat transfer by convection in 3 steps What are the 5 factors that affect the rate of evaporation / condensation? What is a U-value? What is the Specific Heat Capacity of a substance? Which objects are poor absorbers of radiation (i.e. good reflectors)? What is the equation to calculate Specific Heat Capacity (SHC)? What is a vacuum? Which type of radiation can transmit heat in a vacuum? How is heat transmitted by radiation? Which type of materials are the best conductors?

2 1.Temperature 2.Surface area 3.Volume 4.Material 5.Colour 1.Particles in a liquid or gas are heated, causing them to vibrate more 2.This causes this part of the liquid / gas to become less dense, and then rise to the top 3.This pushes the denser, colder liquid/gas to the bottom 1.When particles are heated, they vibrate more 2.This vibration causes nextdoor particles to vibrate more 3.This passes the heat energy down the object Black, matt objects E = m x c x Θ Silver, shiny objects SHC is the amount of energy required to change the temperature of 1kg of the substance by 1°C A value which tells you the rate at which energy is transferred through an object (The lower the U- value, the better it is at insulating) Metals As an electromagnetic wave Radiation A vacuum is when there are no particles present

3 What does the law of ‘conservation of energy’ say? What happens to the waste energy created by objects? Name the 10 different types of energy If a lamp takes in 100J of electrical energy, and puts out 40J of light energy, how much energy is wasted, and as what? If a laptop puts out 30J light energy and 10J sound energy and 15J heat energy, how much electrical energy has gone in? What is the definition of ‘efficiency’ What is the equation to calculate efficiency? What is the equation to calculate energy transferred by an electrical appliance? What two things does the amount of energy transferred to an electrical object depend on? What is the unit of power? How do you calculate the cost of electricity used by an appliance? How do you calculate number of electrical units used by an appliance?

4 60J as heat Heat (thermal), light, sound, magnetic, elastic potential, gravitational potential, nuclear, electrical, chemical, kinetic It is transferred to the surroundings, which become warmer. It becomes increasingly spread out. Energy cannot be created or destroyed, only transformed E = P x t (E = energy P = power T = time) The proportion of energy supplied that is transferred to useful energy 55J Units used is the same as energy transferred (kWh), so we use the same equation: E = P x t Total cost = units used x cost per unit kWh The power of the appliance, and the time it’s left on for (E = P x t)

5 Which type of power station has the shortest start up time? What are the advantages of pump- system power stations? Name the fossil fuels used in power stations to heat water Name the nuclear fuels used to heat water in power stations What do step-up transformers do? Put these in order to describe a power station: Turbine, Heat, Generator, Steam Name one advantage and one disadvantage to burning fossil fuels in power stations Name one advantage and one disadvantage to using nuclear fuels in power stations What is the National Grid? What do step-down transformers do? Name 5 renewable energy sources What are the main disadvantages of renewable energy sources?

6 Uranium and Plutonium Coal, oil and gas They can store energy not used in slow periods to meet demands in peak periods Fossil fuel (gas-fired) power stations have the shortest start up time Advantage: do not produce carbon dioxide or sulphur dioxide Disadvantage: the waste remains radioactive for years and must be stored safely Advantage: produce a lot of heat energy Disadvantage: non- renewable / release carbon dioxide / create pollution Heat, Steam, Turbine, Generator Step-up transformers decrease the current of the electricity flowing in the power cables in the national grid. They do this by increasing the voltage. This reduces energy losses. Expensive to set up, infrequent production of electricity, visual and noise pollution, destruction of natural habitats Solar, geothermal, wave, tidal, hydroelectric and wind Step-down transformers do the opposite of step-up transformers. They reduce the voltage of the electricity coming from the national grid by increasing the current. This makes it a safe voltage for household use. A Network of power cables and power stations that produce and transport electricity around the country to homes and businesses

7 What is the difference between longitudinal and transverse waves? What are compression and rarefaction in a longitudinal wave? What is amplitude?What is wavelength? What are crests and troughs in transverse waves? Name, in order from smallest wavelength to biggest wavelength, all the waves in the electromagnetic spectrum What is frequency? Which waves can be used for communication purposes? What is the law of reflection? What is the Doppler Effect? What is red shift?What is CMBR?

8 The length of one wave. Measured from two similar points, e.g. middle to middle, crest to crest or trough to trough The height of a wave (from the middle). Shows the volume of a sound wave. Compression: the part of the wave where particles are squashed together Rarefaction: the part of a wave where particles are spread out Longitudinal waves: oscillations are at right angles to the direction of energy transfer Transverse waves: Oscillations are in the same direction as energy transfer Radio, Micro, Infra- Red and Visible The number of waves passing a point in one second Radio Microwave Infra-Red Visible UV X-Rays Radio waves Gamma Crests are the highest points in a wave. Troughs are the lowest points in a wave. Cosmic Microwave Background Radiation. It is radiation left over from the Big Bang that still exists today. There is an increase in the wavelength of light coming from distant galaxies. This means they are moving away from us. When the wave source moves away from the observer, the wavelength increases and frequency decreases. When the wave source moves towards the observer, the wavelength decreases and frequency increases. The angle of incidence is the same as the angle of reflection


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