Electric Fields problem: Can someone please check my work?

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goooogle
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"a +4nC charge is 6/0 cm along a horizontal line toward the right of a -3nC charged object. Determine the E field at a point 4.0 cm to the left of the negative charge."

From what I understand, it goes Point ___ 4cm ____ (-3nC) _____ 6cm ____ (+4nC)

Using that, I got the answer to be -14.75 nC but I'm very unsure of myself. Can someone check?
 
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goooogle said:
"a +4nC charge is 6/0 cm along a horizontal line toward the right of a -3nC charged object. Determine the E field at a point 4.0 cm to the left of the negative charge."

From what I understand, it goes Point ___ 4cm ____ (-3nC) _____ 6cm ____ (+4nC)

Using that, I got the answer to be -14.75 nC but I'm very unsure of myself. Can someone check?
Hello goooogle. Welcome to PF !

You have the layout correct.

Can you explain how you got that answer?

For sure, the units are not correct.
 
SammyS said:
Hello goooogle. Welcome to PF !

You have the layout correct.

Can you explain how you got that answer?

For sure, the units are not correct.

Well, I did

((K)(-3 x10^-9))/(.04^2) + ((K)(4x10^-9)/(.1^2) which gets me -13275. From there, I did -13725 = ((K)(X))/(.1^2) which comes out to -14.75 nano coloumbs.

Is that right? Is .1 the right distance for the second part?
 
goooogle said:
Well, I did

((K)(-3 x10^-9))/(.04^2) + ((K)(4x10^-9)/(.1^2) which gets me -13275. From there, I did -13725 = ((K)(X))/(.1^2) which comes out to -14.75 nano coloumbs.

Is that right? Is .1 the right distance for the second part?
For the first part: What is the direction of the E-field due to the negative charge? What is the direction of the E-field due to the positive charge?

What are the units of the number -13275 ?What second part. You didn't mention a second part in the question.
 
SammyS said:
For the first part: What is the direction of the E-field due to the negative charge? What is the direction of the E-field due to the positive charge?

What are the units of the number -13275 ?What second part. You didn't mention a second part in the question.

The direction for the E-field because of the negative charge would be to the right, so +? In that case, it'd be 16875 - 3600, which is +13275. So I understand that, I think. The units are N/C. The second part was just desperation, trying to find a step I missed.

So I take it +13275 N/C is my final answer?
 
goooogle said:
The direction for the E-field because of the negative charge would be to the right, so +? In that case, it'd be 16875 - 3600, which is +13275. So I understand that, I think. The units are N/C. The second part was just desperation, trying to find a step I missed.

So I take it +13275 N/C is my final answer?
Your result looks okay for magnitude, units, and direction. Be sure to round any result that is to be presented as a final answer to the correct number of significant figures.
 
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