Electric Fields problem: Can someone please check my work?

AI Thread Summary
The discussion revolves around calculating the electric field at a point 4.0 cm to the left of a -3nC charge, with a +4nC charge located 6 cm to the right. The initial calculation yielded -14.75 nC, which was later corrected to +13275 N/C after addressing the direction of the electric fields from both charges. Participants confirmed the layout of the problem and clarified the correct units and direction for the electric field. The final answer was affirmed, emphasizing the importance of significant figures in the result. Overall, the calculations and understanding of electric field direction were validated.
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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