Angle subtended by arc. [on hold]











up vote
0
down vote

favorite












consider the segment of a circle. I know the arc length and the width of the segment (the line connecting the end points of the arc). I donot know the radius. But angle subtended varies between 0 and 180 degrees. how can i find the radius of the arc for various width of the segment while the arc length remains constant ?










share|cite|improve this question







New contributor




gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











put on hold as off-topic by user10354138, user302797, José Carlos Santos, ancientmathematician, Rebellos 2 days ago


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – user10354138, user302797, José Carlos Santos, ancientmathematician, Rebellos

If this question can be reworded to fit the rules in the help center, please edit the question.













  • What do you know about the relationship between radius, arc and chord length to solve this problem? Please share your thoughts to avoid down votes.
    – Phil H
    Nov 20 at 15:18















up vote
0
down vote

favorite












consider the segment of a circle. I know the arc length and the width of the segment (the line connecting the end points of the arc). I donot know the radius. But angle subtended varies between 0 and 180 degrees. how can i find the radius of the arc for various width of the segment while the arc length remains constant ?










share|cite|improve this question







New contributor




gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











put on hold as off-topic by user10354138, user302797, José Carlos Santos, ancientmathematician, Rebellos 2 days ago


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – user10354138, user302797, José Carlos Santos, ancientmathematician, Rebellos

If this question can be reworded to fit the rules in the help center, please edit the question.













  • What do you know about the relationship between radius, arc and chord length to solve this problem? Please share your thoughts to avoid down votes.
    – Phil H
    Nov 20 at 15:18













up vote
0
down vote

favorite









up vote
0
down vote

favorite











consider the segment of a circle. I know the arc length and the width of the segment (the line connecting the end points of the arc). I donot know the radius. But angle subtended varies between 0 and 180 degrees. how can i find the radius of the arc for various width of the segment while the arc length remains constant ?










share|cite|improve this question







New contributor




gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











consider the segment of a circle. I know the arc length and the width of the segment (the line connecting the end points of the arc). I donot know the radius. But angle subtended varies between 0 and 180 degrees. how can i find the radius of the arc for various width of the segment while the arc length remains constant ?







trigonometry mathematical-modeling






share|cite|improve this question







New contributor




gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|cite|improve this question







New contributor




gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|cite|improve this question




share|cite|improve this question






New contributor




gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









asked Nov 20 at 14:43









gokul prassad

1




1




New contributor




gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





New contributor





gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






gokul prassad is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.




put on hold as off-topic by user10354138, user302797, José Carlos Santos, ancientmathematician, Rebellos 2 days ago


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – user10354138, user302797, José Carlos Santos, ancientmathematician, Rebellos

If this question can be reworded to fit the rules in the help center, please edit the question.




put on hold as off-topic by user10354138, user302797, José Carlos Santos, ancientmathematician, Rebellos 2 days ago


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level." – user10354138, user302797, José Carlos Santos, ancientmathematician, Rebellos

If this question can be reworded to fit the rules in the help center, please edit the question.












  • What do you know about the relationship between radius, arc and chord length to solve this problem? Please share your thoughts to avoid down votes.
    – Phil H
    Nov 20 at 15:18


















  • What do you know about the relationship between radius, arc and chord length to solve this problem? Please share your thoughts to avoid down votes.
    – Phil H
    Nov 20 at 15:18
















What do you know about the relationship between radius, arc and chord length to solve this problem? Please share your thoughts to avoid down votes.
– Phil H
Nov 20 at 15:18




What do you know about the relationship between radius, arc and chord length to solve this problem? Please share your thoughts to avoid down votes.
– Phil H
Nov 20 at 15:18










1 Answer
1






active

oldest

votes

















up vote
0
down vote













For an arc of aperture $2alpha$ and unit radius (hence angle and arc length are equal), the chord length is $2sinalpha$.



Hence, the ratio of the arc over the chord is



$$frac ac=frac{sinalpha}{alpha}=text{sinc }alpha.$$



When you know this ratio, you can obtain the half-angle by



$$alpha=text{sinc}^{-1}frac ac,$$ but this inverse function is not commonly available and you should solve the equation numerically.



Then



$$r=frac aalpha.$$





For small angles, you can use



$$text{sinc }alphaapprox 1-frac{alpha^2}6+frac{alpha^4}{120}$$ and solve the biquadratic equation.






share|cite|improve this answer




























    1 Answer
    1






    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes








    up vote
    0
    down vote













    For an arc of aperture $2alpha$ and unit radius (hence angle and arc length are equal), the chord length is $2sinalpha$.



    Hence, the ratio of the arc over the chord is



    $$frac ac=frac{sinalpha}{alpha}=text{sinc }alpha.$$



    When you know this ratio, you can obtain the half-angle by



    $$alpha=text{sinc}^{-1}frac ac,$$ but this inverse function is not commonly available and you should solve the equation numerically.



    Then



    $$r=frac aalpha.$$





    For small angles, you can use



    $$text{sinc }alphaapprox 1-frac{alpha^2}6+frac{alpha^4}{120}$$ and solve the biquadratic equation.






    share|cite|improve this answer

























      up vote
      0
      down vote













      For an arc of aperture $2alpha$ and unit radius (hence angle and arc length are equal), the chord length is $2sinalpha$.



      Hence, the ratio of the arc over the chord is



      $$frac ac=frac{sinalpha}{alpha}=text{sinc }alpha.$$



      When you know this ratio, you can obtain the half-angle by



      $$alpha=text{sinc}^{-1}frac ac,$$ but this inverse function is not commonly available and you should solve the equation numerically.



      Then



      $$r=frac aalpha.$$





      For small angles, you can use



      $$text{sinc }alphaapprox 1-frac{alpha^2}6+frac{alpha^4}{120}$$ and solve the biquadratic equation.






      share|cite|improve this answer























        up vote
        0
        down vote










        up vote
        0
        down vote









        For an arc of aperture $2alpha$ and unit radius (hence angle and arc length are equal), the chord length is $2sinalpha$.



        Hence, the ratio of the arc over the chord is



        $$frac ac=frac{sinalpha}{alpha}=text{sinc }alpha.$$



        When you know this ratio, you can obtain the half-angle by



        $$alpha=text{sinc}^{-1}frac ac,$$ but this inverse function is not commonly available and you should solve the equation numerically.



        Then



        $$r=frac aalpha.$$





        For small angles, you can use



        $$text{sinc }alphaapprox 1-frac{alpha^2}6+frac{alpha^4}{120}$$ and solve the biquadratic equation.






        share|cite|improve this answer












        For an arc of aperture $2alpha$ and unit radius (hence angle and arc length are equal), the chord length is $2sinalpha$.



        Hence, the ratio of the arc over the chord is



        $$frac ac=frac{sinalpha}{alpha}=text{sinc }alpha.$$



        When you know this ratio, you can obtain the half-angle by



        $$alpha=text{sinc}^{-1}frac ac,$$ but this inverse function is not commonly available and you should solve the equation numerically.



        Then



        $$r=frac aalpha.$$





        For small angles, you can use



        $$text{sinc }alphaapprox 1-frac{alpha^2}6+frac{alpha^4}{120}$$ and solve the biquadratic equation.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Nov 20 at 15:18









        Yves Daoust

        121k668216




        121k668216















            Popular posts from this blog

            Tonle Sap (See)

            I get strange results when I access the Sqlitedatabase with Unity C# via XAMPP

            Guatemaltekische Davis-Cup-Mannschaft