Help with vector algebra getting an undefined answer

In summary, to determine the magnitude of F that will cause the net effect of the three forces to act vertically, vector algebra was used to set up the equation for the x and y components of the net force. By taking the square root of the sum of the squares of the x and y components, the resultant force could be calculated. However, there was an error in setting up the equation to show that the net force was acting vertically, as the arctan of 90 is undefined. The problem was ultimately solved by simplifying the equation and realizing that the x component of the resultant force would be zero.
  • #1
HeJind
5
0

Homework Statement



Determine the magnitude of F that will cause the net effect of
the three forces to act vertically.

In the diagram there are three bolts (I'll refer to the first two as B1 and B2), and the third bolt, F, is undefined. F acts 45 degrees northeast of the horizontal, B1 is 410N and acts 30 degrees west of north, and B2 is 200N and acts 10 degrees north of west.

The Attempt at a Solution



I used vector algebra to set up the equation, diving what vetors into x & y components. The net force in the x direction would be equivalent to -410cos(30) - 200cos(10) + "F"cos(45), and the net Y would be 410sin(30) + 200sin(40) + "F"sin(45).

adding the squares of X & Y and taking the square root of the sum would obviously give me the resultant. However, here's where I run into a problem.

When I set up the equation to show that the net force was acting vertically, I got 90 = arctan(Ry/Rx) . This would mean that Ry/Rx = Tan(90) but tan90 is obviously undefined. What am I doing wrong?
 
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  • #2
If its acting vertically then what would the x component of the resultant force be?
 
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  • #3
Ah...makes sense now. I greatly over complicated this problem. Thank you!
 

1. Why am I getting an undefined answer when working with vector algebra?

There are a few possible reasons for getting an undefined answer when working with vector algebra. One common reason is that there may be a division by zero error in your calculations. Another possibility is that the vectors you are working with may be parallel or anti-parallel, meaning they have the same or opposite direction, which can lead to undefined results in some operations.

2. How can I avoid getting an undefined answer when working with vector algebra?

To avoid getting an undefined answer, it is important to ensure that your vectors are not parallel or anti-parallel. This can be done by checking the direction of the vectors and making sure they are not exactly the same or exactly opposite. Additionally, double check your calculations to make sure there are no division by zero errors.

3. Can I still use vector algebra if I am getting undefined answers?

Yes, vector algebra can still be used even if you are getting undefined answers. However, it is important to identify the source of the undefined result and make sure it does not affect the overall accuracy of your calculations. If necessary, you may need to use alternate methods to solve the problem or adjust your approach to the problem.

4. How do I know if my vector algebra calculations are correct?

To ensure the accuracy of your vector algebra calculations, it is important to double check your work and use multiple methods to solve the problem. You can also compare your results to known solutions or use software or calculators to verify your answers. If you are consistently getting undefined answers, it may be necessary to review the concepts and principles of vector algebra to identify any errors in your approach.

5. Are there any resources available to help with vector algebra and understanding undefined answers?

Yes, there are many resources available online and in textbooks to help with vector algebra and understanding undefined answers. You can also seek help from a tutor or instructor who can provide personalized assistance and clarify any confusing concepts. Additionally, practicing and working through various problems can help improve your understanding of vector algebra and how to avoid or handle undefined answers.

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