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Waves

  • 08-09-2004 5:47pm
    #1
    sci0x
    Closed Accounts Posts: 2,319 ✭✭✭


    Hey guys,

    I just need a little help with this physics question. It would be great if you could do it so I could learn how to do it. I just need to know how to do the questions marked (i) (ii) and (iii). The question is above this. I know how to do most of them just this caught me out. Thanks.

    The question is here.

    Thanks again,
    Denis


Comments

  • #2
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 93,563 Mod ✭✭✭✭Capt'n Midnight


    Radiowaves of frequency 30KHz ...

    (i) Calculate the wavelength


    How exactly did this catch you out ???
    c=lambda.f

    c as in E=Mc2
    f as in frequency
    lamdba would be a wavelength


  • #3
    Boston
    Closed Accounts Posts: 17,163 ✭✭✭✭Boston


    Capt'n Midnight wrote:
    Radiowaves of frequency 30KHz ...

    (i) Calculate the wavelength


    How exactly did this catch you out ???
    c=lambda.f

    c as in E=Mc2
    f as in frequency
    lamdba would be a wavelength

    Maybe he didn't know that Radiowaves travel at the speed of light? Check out the electromagnetic spectrum for the rest.

    Edit:

    2) 1500km plus half the wavelenght (half because you want destructive interference)

    3) (1500 + plus lammda/2) Squared / 4 - (1500)squared / 4 = h squared.

    This stuff is rather basic, Leaving cert are we talking?


  • #4
    sci0x
    Closed Accounts Posts: 2,319 ✭✭✭sci0x


    Yep, i knew how to do (i) but 10,000km didn't sound right. It was (ii) and (iii) that were catching me out. But sure its so easy after its explained. Thanks guys.


  • #5
    ApeXaviour
    Registered Users, Registered Users 2 Posts: 5,523 ✭✭✭ApeXaviour


    That was 2002 right? Yeah I'da got an A1 if I knew what coherant meant, but I didn't so I didn't. Ah that's life and as long as I get a 2.1 or higher in my degree then I dinna give a rats ass about the leaving.


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