Where am I going wrong with this vector addition?

In summary, the conversation discusses a problem involving force from an electric charge and adding vectors. The speaker is following an example in their book and is getting a different answer than what is given in the book. They suspect a typo in the given answer and suggest that the minus sign on the i coefficient may have been placed incorrectly.
  • #1
guyvsdcsniper
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Homework Statement
Three charged particles with q1 = -50 nC, q2 = +50 nC, and q3 = +30 nC are placed on the corners of the 5.0 cm X 10.0 cm rectangle shown in Figure 22.18lkl. What is the net force on charge q3 due to the other two charges? Give your answer both in component form and as a
magnitude and direction
Relevant Equations
F=kq1q2/r^2
I am following along with an example in my book regarding force from an electric charge. I understand the process but I believe I am getting something wrong when it comes to adding the vectors.

Essentially, F13 is equal to -1.35*10^-3 j and when I add that to the j component of F23 which is 9.67*10^-4 J I am getting -3.84*10^-4. The book is giving positive 3.84*10^-4. I have highlighted the values in the PDF attached. Could someone help me understand why it would be positive?
 

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  • #2
Clearly a typo in the given answer.
Maybe the minus sign on the i coefficient was supposed to be outside the parentheses.
 
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FAQ: Where am I going wrong with this vector addition?

What is vector addition?

Vector addition is the process of combining two or more vectors to create a new vector. It involves adding the magnitudes and directions of the individual vectors to determine the magnitude and direction of the resulting vector.

How do I know if I am doing vector addition correctly?

You can check your work by using the parallelogram method or the head-to-tail method. If the resulting vector is the diagonal of the parallelogram or the vector that connects the head of the first vector to the tail of the second vector, then you have done the addition correctly.

What are some common mistakes when performing vector addition?

Some common mistakes include not properly aligning the vectors, forgetting to account for the direction of the vectors, and not using the correct units for the vectors.

How do I handle vectors with different dimensions?

Vectors with different dimensions cannot be added together. If you encounter this situation, you can use the components of the vectors to perform the addition. Alternatively, you can convert all vectors to the same dimension before adding them together.

Can I add more than two vectors at a time?

Yes, you can add as many vectors as you want at a time. You can do this by first adding two vectors and then adding the resulting vector to another vector, and so on. Alternatively, you can use the component method to add multiple vectors at once.

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