Hi Gary, As I noted in my post, I made a fatal error in my calculations. Check out Dr. Math’s FAQ on Circle Segments, it has the correct equations.

]]>Hi Nurm,

I am trying to follow your solution to the radius given chord and arc angle.

I am using objective c since I want to use a computer to display the answers.

So far having programmed the formula, I end up with an answer which is wrong

Using 20 for chord length and 25 for arc angle, I end up with 14.564 as the radius.

Can you help me decide what’s gone wrong

Each step produces results like this

A= 225

B =4.94066 e-324

C = 1.80108 e-226

D = 2.07401 e-183

F = 0.004438

G = -9544371.768889

X = 212.118924

R = 14.564303

I don’t really understand your formula and think I have programmed the steps properly, but hope by studying the outputs of each equation you can point me to the mistake in my calculation

Many thanks

]]>@arnav: Have a look at the circle calculator on the 1728 website, it has an option to calculate this.

]]>i need to calculate the arc height from the centre of chord of length 100cm and arc lenght 101 cm. so help me to solve in step by step process to get the final answer.

]]>Hello,

I dont understand what – is supposed to stand for in the equation C² = 2 r² (1 – cos(θ))) or anywhere else on the site. Is it maybe a type that i dont have? or an axiom that I dont know?

thans in advance

m

]]>@Jose and tankguy,

Unfortunately I just don’t have the time to help everyone that posts on my blog, I suggest that you make a scale model of what you’re trying to achieve so that you can work out the measurements before you start on full scale production. Additionally I suggest that you try some of the resources linked to on this page, as they will probably help out too.

]]>If I am laying out a segmented head, say a 30 foot diameter hemisphere with 15 segments. How do I solve for the right angle on 2 degree increments on my LDC. Lenght down center. Solving for the right angle every 2 degrees will give me the proper measurements to lay the segment out flat for cutting the blank before pressing. I am not strong on math. I need a simple formula. Thank you for your help.

]]>Please update the link in your article from http://mcraefamily.com/MathHelp/FactoringCubic1.htm to http://2000clicks.com/MathHelp/FactoringCubic1.htm . The reason is I had to shut down the mcraefamily.com website, since it was the victim of a distributed delinal of service attack. Thank you.

]]>Hi,

I have a challenge I am designing a new 1200mm Heavy duty open end Spanner and going off a 36mm open ender I need the radius of the three different arcs used in the shape of the open end head of the spanner, how can I find the Radius fron the given arcs?

Regards

Jose

Thanks that’s just the job. cheers Paul

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