(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hello! I've run into a problem at work and need a quick solution! Basically I need to work out the cut size of a curved bar. I have the chord length (650mm) and the radius' (1335mm) Obviously i need to calculate the inner most angle, then multiply my diameter by pi, divide by 360 then multiply by my new found angle to find arc length

2. Relevant equations

Cosine rule A=b[itex]^{2}[/itex]+c[itex]^{2}[/itex]-a[itex]^{2}[/itex][itex]/[/itex]2bc

C=∏d

3. The attempt at a solution

obviously c and b are both equal at 1335mm. so the triangle becomes isosceles

Arc length = ∏x2670/360 x (1335[itex]^{2}[/itex]+1335[itex]^{2}[/itex]- 650[itex]^{2}[/itex]/2x1335x1335)[itex]^{cos-1}[/itex]

this equation leaves us at 28.17°

then (2670x∏/360)x28.17=656mm

Only 6mm gain on the arc? is this normal? please help!

many thanks, connor.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Cosine rule help!

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