Force vector - Value and uncertainty for components

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SUMMARY

The discussion focuses on calculating the components of a force vector in polar coordinates, specifically F1 = 50±2 N at an angle of 30±2 degrees. The key equations used are Fx = F cos(θ) and Fy = F sin(θ), with the necessity of converting degrees to radians for accurate calculations. The participant seeks assistance in applying partial derivatives to determine the uncertainties in both Fx and Fy, utilizing the chain rule for differentiation.

PREREQUISITES
  • Understanding of polar coordinates and vector representation
  • Knowledge of trigonometric functions (sine and cosine)
  • Familiarity with calculus, specifically partial derivatives and the chain rule
  • Ability to convert angles from degrees to radians
NEXT STEPS
  • Study the application of partial derivatives in uncertainty analysis
  • Learn about error propagation in vector calculations
  • Review the process of converting angles from degrees to radians
  • Practice solving similar problems involving force vectors and uncertainties
USEFUL FOR

Students in physics or engineering courses, particularly those focusing on mechanics and vector analysis, as well as educators seeking to enhance their teaching methods in these topics.

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Homework Statement



A force in polar coordinates is given by F1 = 50±2 N at the angle 30±2 degrees.

Find the value and uncertainty for Fx and Fy

Since force is a vector, there will be an error in both its magnitude and direction...

angle calculations must be in RADIANS...

[itex] 30\frac{+}{}2 degrees = \frac{\pi}{6} \frac{+}{} \frac{\pi}{90}<br /> [/itex]

Homework Equations



Fx = F cos(θ)
Fy = F sin(θ)

The Attempt at a Solution



Fx is a function of both F and θ so i took the derivative of Fx = F cos(θ) using the chain rule.

[itex] <br /> F_{x-error} = cos(\theta)\frac{dF_x}{dF} - F(sin(\theta))\frac{dF_x}{d\theta}<br /> [/itex]

I did the same for Fy

[itex] <br /> F_{y-error}= sin(\theta)\frac{dF_y}{dF} + F(cos(\theta))\frac{dF_y}{d\theta}<br /> [/itex]Can i please get some help with what to do next. I am a little lost and confused :(

Thanks for any help :)
 
Last edited:
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Can anyone suggest anything for this?

I know it deals with partial derivatives and everything, I am just not exactly sure about all that stuff and what to do for this question and my professor sure as heck doesn't explain it at all :(
 

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