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    can someone tell me the differences (and similarities) between electric and magnetic fields
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    another one...

    2 plates 25mm apart. top plate is at 3000V, the bottom plate at 0V.


    Sketch a graph of how the force on an electron varies with the distance of the electron from the bottom plate...
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    (Original post by jonas123)
    another one...

    2 plates 25mm apart. top plate is at 3000V, the bottom plate at 0V.


    Sketch a graph of how the force on an electron varies with the distance of the electron from the bottom plate...
    I think electromagnetic attractions have the same inverse square law as gravitational ones do? In that case you'd get this curve :
    (I think)
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    (Original post by jonas123)
    can someone tell me the differences (and similarities) between electric and magnetic fields
    Electric Fields
    Can be due to a single charge
    Act on all charges, stationary or moving
    Can be radial
    Produce force parallel to field

    Magnetic fields
    Cannot be due to single poles
    Only act on moving charges
    Lines ust be closed loops
    Produce a force perpendicular to field
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    hehe! is evryone doing U5 Jan O4 Paper?! Cuxz both of these questions are on there!

    The graph is a straight line graph, but not through the origin. It hit's the y-axis at the value you calculated earlier in question.
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    (Original post by Hoofbeat)
    hehe! is evryone doing U5 Jan O4 Paper?! Cuxz both of these questions are on there!

    The graph is a straight line graph, but not through the origin. It hit's the y-axis at the value you calculated earlier in question.
    yes thats what i thought as well. the force is constant becausethe electric field strength is constant
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    yeh these are questions from that paper...i found it much harder than any of the other past papers
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    (Original post by scarlet ibis)
    yes thats what i thought as well. the force is constant becausethe electric field strength is constant
    Does it not get stronger at the electron becomes closer?
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    Yeah the graph is a horizontal line (uniform electric field so same force everywhere)

    I was a little confused by top and bottom - wasn't sure if they were one above the other or just talking diagrams - I couldn't decide whether to worry about weight in the acceleration/speed bit at the end.
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    (Original post by mik1a)
    Does it not get stronger at the electron becomes closer?
    No, E = F/q = V/d but d is just seperation of the plates. It's a uniform electric field so F = Vq/d which are all constants
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    how come force is max at the 0V plate and 0 at the 3000V plate?

    F = Vq/d so shouldn't the force be max at the 3000V plate (where V=3000) or is the voltage not 3000V at the 3000V plate?
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    no its definately a straught line. i checked the markscheme
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    (Original post by jonas123)
    how come force is max at the 0V plate and 0 at the 3000V plate?

    F = Vq/d so shouldn't the force be max at the 3000V plate (where V=3000) or is the voltage not 3000V at the 3000V plate?
    V is the potential difference, d is the seperation of the plates. Force is the same anywhere in a uniform field.
 
 
 
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