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    (Original post by Mathemagician)
    no, he is talking about electric field strength and not electric potential :p:
    nope, he says "So when distance from the conducting sphere doubles the electric potential falls by a factor of 4?"

    which was wrong.
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    (Original post by Revenged)
    Nope it's an inverse square law

    V = kQ/r
    but V = kQ/r is not inverse SQUARE.. its just inverse.
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    but the formula was right, E = kQ/r^2
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    So, the electric potential tells you the potential difference at one point in a electric field but could you use this following formula in both the situations?

    V = kQ/r
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    (Original post by Revenged)
    So, the electric potential tells you the potential difference at one point in a electric field but could you use this following formula in both the situations?

    V = kQ/r
    it is analogous to gravitational potential.
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    (Original post by Revenged)
    So, the electric potential tells you the potential difference at one point in a electric field but could you use this following formula in both the situations?

    V = kQ/r
    that is if you have a charged sphere for example while if you want to find the electrical potential between two conducting parrallel plates you use Ex=V
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    (Original post by mik1w)
    but the formula was right, E = kQ/r^2
    this is the electrical field strength,so when distance doubles the electrical field strenth decreases by the factor of 1/4
    while for electrical potential which is V you know so that V=KQ/r so that when the distance is doubled the electrical potential halves though I don't think that this equation is requierd from us hmmm. also the electrical potential energy=KQq/r
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    (Original post by habosh)
    this is the electrical field strength,so when distance doubles the electrical field strenth decreases by the factor of 1/4
    while for electrical potential which is V you know so that V=KQ/r so that when the distance is doubled the electrical potential halves though I don't think that this equation is requierd from us hmmm. also the electrical potential energy=KQq/r
    yeah. It is required for OCR B though.
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    and equipotential lines,are lines where there is no change in the energy.the energy along them is constant and they are perpendicular to the field lines
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    ummm! sorry yes it is
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    ok... so

    For a parallel plates

    E = V/d

    therefore if i rearrange that to

    V = Ed (i get what you have)

    For a conducting sphere, however,

    V = kQ/r
    E = kQ/r^2

    Is that right?
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    (Original post by Mathemagician)
    yeah. It is required for OCR B though.
    also the transformer thingie..to drow flux graphs...etc
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    (Original post by Revenged)
    ok... so

    For a parallel plates

    E = V/d

    therefore if i rearrange that to

    V = Ed (i get what you have)

    For a conducting sphere, however,

    V = kQ/r
    E = kQ/r^2

    Is that right?
    yep...sure it's for a conducting other wise we wont have an electrical field at all
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    'electrical potential energy=KQq/r'

    What's that?

    Looks like Newton's Law of something
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    for 2 spheres, what is the electric field strength and the electric potential?

    edit: what are the formulae?
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    (Original post by Revenged)
    'electrical potential energy=KQq/r'

    What's that?

    Looks like Newton's Law of something
    yeah, its similar to Newtons law of gravitation.
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    electric potential? it's to work out electric field strength?
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    (Original post by Revenged)
    'electrical potential energy=KQq/r'

    What's that?

    Looks like Newton's Law of something
    yeah,this is not requierd from edexcel though dont panic for example
    F(electrical)=KQq/r^2
    right?
    now the work done=electrical pontential enegry
    so W=Fx=PEe
    so
    as x=r then
    Fr=KQqr/r^2
    so then the r/r^2=1/r
    so KQq/r=Pe
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    (Original post by habosh)
    this is the electrical field strength,so when distance doubles the electrical field strenth decreases by the factor of 1/4
    while for electrical potential which is V you know so that V=KQ/r so that when the distance is doubled the electrical potential halves though I don't think that this equation is requierd from us hmmm. also the electrical potential energy=KQq/r
    no lowercase q there, V=kQ/r
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    (Original post by mik1w)
    no lowercase q there, V=kQ/r
    no that was the electrical potential energy not the electrical potential
    PE=KqQ/r
    and V=QK/r
 
 
 
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