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    Which electromagnetic wave has the highest frequency?
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    In longitudinal waves, what is it that is compressed and is in rarefaction? - I don't know the answer so please help haha
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    (Original post by Dizgurl)
    The direction of the vibrations are parallel to the direction of energy transfer in the wave.

    What is payback time?
    Calculate the payback time of an insulating jacket that costs £250, but you save yearly £100.
    Payback time is the amount of time taken to pay the material used you bought and the answer is 2.5 years because 250/100=2.5
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    (Original post by Dizgurl)
    The direction of the vibrations are parallel to the direction of energy transfer in the wave.

    What is payback time?
    Calculate the payback time of an insulating jacket that costs £250, but you save yearly £100.
    payback time is the time it takes for an energy saving installation to pay back the amount of money it took for you to pay for it.

    2 and a half years

    What is the doppler effect
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    (Original post by leozango)
    which electromagnetic wave has the highest frequency?
    gamma rays
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    (Original post by jazz_xox_)
    In longitudinal waves, what is it that is compressed and is in rarefaction? - I don't know the answer so please help haha
    'Compression happens when molecules are forced, or pressed, together. Rarefaction is just the opposite, it occurs when molecules are given extra space and allowed to expand'- Bitesize
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    (Original post by jazz_xox_)
    Rarefaction is where the wavelengths are more spread out, and compression is where they are closer together.

    (Am I right by saying it is the wavelengths that are spread out?)


    Q: in a longitudinal wave, which direction are the vibrations, to the direction of energy transfer in the wave?
    I think you're meant to say particles Instead of wavelength. But I'm not 100% sure.

    Oscillations are parallel to the direction of energy transfer in a longitudinal wave.
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    (Original post by CaSama9)
    In longitudunal waves, the vibrations of the wave are travelling parralel to the direction of energy transfer.

    T transverse
    W waves
    A are
    T technically

    P Perpendicular to the
    D direction of
    E energy
    T transfer

    Advantages and disadvantages of over head and underground cables?


    Overhead cables:
    + lower setup cost
    +easy to access
    +minimal disturbance to land
    - can be affected by weather
    -visual pollution
    -some people believe it affects health

    Underground cables
    + no visual pollution
    + not affected as much by weather
    - high maintenance costs
    - high set up costs


    Q: What does the rate of diffraction depend on?
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    Quick question
    do you need to know the processes of all the renewable processes ?
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    (Original post by jazz_xox_)
    Overhead cables:
    + lower setup cost
    +easy to access
    +minimal disturbance to land
    - can be affected by weather
    -visual pollution
    -some people believe it affects health

    Underground cables
    + no visual pollution
    + not affected as much by weather
    - high maintenance costs
    - high set up costs


    Q: What does the rate of diffraction depend on?
    Size of the gap
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    (Original post by Mahrez)
    'Compression happens when molecules are forced, or pressed, together. Rarefaction is just the opposite, it occurs when molecules are given extra space and allowed to expand'- Bitesize
    Thank you! I didn't know it was the molecules
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    (Original post by nisha.sri)
    Quick question
    do you need to know the processes of all the renewable processes ?
    Yes, somewhat. Just know very briefly what happens, the advantages and disadvantages would be more important
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    (Original post by LeoZango)
    Which electromagnetic wave has the highest frequency?
    gamma

    which which electromagnetic wave has the highest wave length?
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    (Original post by LeoZango)
    Which electromagnetic wave has the highest frequency?
    Gamma Rays

    Q: which wave from the electromagnetic spectrum is used for communication, and how and why is it used, with examples. [3]
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    (Original post by CaSama9)
    gamma

    which which electromagnetic wave has the highest wave length?
    Radio waves


    Q: state the law of conservation of energy
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    (Original post by jazz_xox_)
    Radio waves


    Q: state the law of conservation of energy
    energy cannot be created or destroyed but transfered
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    (Original post by jazz_xox_)
    Yes, somewhat. Just know very briefly what happens, the advantages and disadvantages would be more important
    Oh ok thank you
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    (Original post by jazz_xox_)
    Gamma Rays

    Q: which wave from the electromagnetic spectrum is used for communication, and how and why is it used, with examples. [3]
    Well radiowaves are used for communications for example TV signals or radio signals, they're usualy bounced off, diffracted off the ionsphere if the wave lengths are short, if theyre long theyre bend towards the earth to the reciever.

    But Microwaves are used for satellite communications, bounced off satellites, and um it's used so that information is transfered from one place to another, e,g phones, satellite phones haha

    Describe and explain how a nucleur power station works? 4 marks
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    (Original post by jazz_xox_)
    Radio waves


    Q: state the law of conservation of energy
    energy cant be created or destroyed but can be dissipitated or transformed from one form to another.

    What is CMBR and what does it suggest?
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    (Original post by TeenPolyglot)
    Step up transformers increase the voltage within the National Grid to 132,000V so less energy is lost along the cables.
    The voltage is then stepped down by the step down transformers to 230V to make it safe for houses.

    What is a U-Value?
    How good an insulator the material is.
    Is this the correct definition to use in the exam by the way, because i've found there to be a few different ways of wording it?

    Q. Why does sound travel faster in denser materials?
 
 
 
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