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Physics Question

  • 17-05-2012 6:30pm
    #1
    checkcheek
    Registered Users, Registered Users 2 Posts: 223 ✭✭


    Did anybody do the physics mock with the X-rays as question 9


    If anyone did do u know the answer for the maths part!! I have it done right( I hope) but im not sure!!


Comments

  • #2
    Wesc.
    Registered Users, Registered Users 2 Posts: 715 ✭✭✭Wesc.


    Yeah I did :) What you do is let the two energies equal, i.e. let E=hf equal E=QV
    Therefore, you can find f, and sub it into c=f(lambda) to get your answer!

    I got 1.55x10^-11m


  • #3
    temujin
    Closed Accounts Posts: 36 ✭temujin


    i know that's its a bit random but in the questions 1-4, are the axis you use in the graph questions important. i know the "cause" is supposed to go on the x axis but the books and marking schemes do the opposite of each other with mixing up the axis'.
    thanks


  • #4
    Wesc.
    Registered Users, Registered Users 2 Posts: 715 ✭✭✭Wesc.


    temujin wrote: »
    i know that's its a bit random but in the questions 1-4, are the axis you use in the graph questions important. i know the "cause" is supposed to go on the x axis but the books and marking schemes do the opposite of each other with mixing up the axis'.
    thanks

    I always do it your way, that's the correct way I thought? :P Anyways, I've never lost any marks for doing it that way!
    But if 2 things are directly proportional I'm sure you'd still get full marks because the graph will still be a straight line from the origin :)


  • #5
    temujin
    Closed Accounts Posts: 36 ✭temujin


    Wesc. wrote: »
    I always do it your way, that's the correct way I thought? :P Anyways, I've never lost any marks for doing it that way!
    But if 2 things are directly proportional I'm sure you'd still get full marks because the graph will still be a straight line from the origin :)

    thanks.. i thought that it would be fine i just wanted to make sure


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