When does the small angle approximation deviate by more than 1%?

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SUMMARY

The small angle approximation begins to deviate from the exact trigonometric results by more than 1% at angles greater than approximately 11.5 degrees. This conclusion is derived by comparing the approximate formula d = rθ with the exact formula d = 2*r*Sin(θ/2). The deviation can be quantified using the equation 0.01 = |Exact - Approx.|/Exact, leading to the necessity of numerical or graphical methods for isolating θ. It is crucial to convert the angle to degree measure for practical applications.

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  • Understanding of trigonometric functions, specifically sine and cosecant.
  • Familiarity with the small angle approximation in physics and mathematics.
  • Basic knowledge of numerical methods for solving equations.
  • Ability to convert angles between radians and degrees.
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  • Learn numerical methods for solving transcendental equations.
  • Study the properties and applications of the sine function in trigonometry.
  • Explore graphical methods for visualizing trigonometric functions and their approximations.
  • Investigate the implications of the small angle approximation in physics, particularly in mechanics.
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Students in physics and mathematics, educators teaching trigonometry, and anyone interested in the applications of the small angle approximation in real-world scenarios.

Airsteve0
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Homework Statement


Find, by comparison with exact trigonometry, the angle,  (provide a numerical value
in degrees), above which the small angle approximation departs from the exact result by more than 1 percent.


Homework Equations



Approx.: d = s = rθ
Exact: d = 2*r*Sin(θ/2)

The Attempt at a Solution



.01 = |Exact - Approx.|/Exact

(θ/2)*Csc(θ/2) = 1.01


At this point I am unsure of how to isolate for θ. Any tips are greatly appreciated, thanks!
 
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Airsteve0 said:

Homework Statement


Find, by comparison with exact trigonometry, the angle,  (provide a numerical value
in degrees), above which the small angle approximation departs from the exact result by more than 1 percent.


Homework Equations



Approx.: d = s = rθ
Exact: d = 2*r*Sin(θ/2)

The Attempt at a Solution



.01 = |Exact - Approx.|/Exact

(θ/2)*Csc(θ/2) = 1.01

At this point I am unsure of how to isolate for θ. Any tips are greatly appreciated, thanks!
That equation can only be solved numerically or graphically.

Don't forget to change the angle to degree measure.
 

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