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    Could some one help with q13 pls 🙏🏼

    http://filestore.aqa.org.uk/subjects...1-QP-JUN14.PDF
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    I've moved this thread to the Physics Study Help forum where hopefully you'll get more responses
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    (Original post by HG1)
    Could some one help with q13 pls 🙏🏼

    http://filestore.aqa.org.uk/subjects...1-QP-JUN14.PDF
    Are you familiar with Coulomb's law? For two point charges with charges q_1, q_2 of opposite sign positioned a distance r apart, there is an attractive force between the two that satisfies:

    \text{Force}=\dfrac{|q_1q_2|}{4 \pi \epsilon_0r^2}

    Apply this to the case \text{Force} = 0.5F, r=20 to find F in terms of |q_1q_2|. Then apply it to the case \text{Force}=F, r=d, substitute what you found in the previous step, and rearrange to find d.

    Edit: Oh, almost forgot the .
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    (Original post by Farhan.Hanif93)
    Are you familiar with Coulomb's law? For two point charges with charges q_1, q_2 of opposite sign positioned a distance r apart, there is an attractive force between the two that satisfies:

    \text{Force}=\dfrac{|q_1q_2|}{4 \pi \epsilon_0r^2}

    Apply this to the case \text{Force} = 0.5F, r=20 to find F in terms of |q_1q_2|. Then apply it to the case \text{Force}=F, r=d, substitute what you found in the previous step, and rearrange to find d.

    Edit: Oh, almost forgot the .

    Thanks for you're reply would you mind showing me steps of how to get to the answer as I just don't understand the logic ?
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    (Original post by HG1)
    Thanks for you're reply would you mind showing me steps of how to get to the answer as I just don't understand the logic ?
    That formula I gave you *should* look familiar - does it? You really only have to use it twice to get an answer. If you're stuck on the first step, what do you get by putting \text{Force} = 0.5F and r=20 into that formula? Can you make F the subject?

    Then as you know what F is, you can use the formula again but with \text{Force}=F and r=d this time, to get another equation which you can solve for d.

    I'm afraid in general, step-by-step answers are frowned upon in study help. It would be better for you to read my post again and to attempt the steps I outlined. Then post up some working and either myself or someone else will be able to help you further.
 
 
 
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