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# Electric fields question watch

1. Hi, I don't get why they didn't include the negative sign in the calculations for the negative charge? I did this and got the distance as -0.08. This is for b (ii) working. I get why they put the charge as positive in b (i) since its just magnitude. Any help would be greatly appreciated thank you!

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2. I think the negative sign you're looking for is between the brackets.

The resultant potential at that point would be the SUM of the potentials due to the two charges and the sum is zero. They've simply moved the negative sign from the charge to between brackets.

Like saying A + (-B) = A - B
3. (Original post by phys981)
I think the negative sign you're looking for is between the brackets.

The resultant potential at that point would be the SUM of the potentials due to the two charges and the sum is zero. They've simply moved the negative sign from the charge to between brackets.

Like saying A + (-B) = A - B
Oh i see! So you dont set them equal but rather find the resultant of them which would = 0. Ah i get it thank you!

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Updated: February 21, 2018
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