Second Moment of Area - semicircular groove in a beam?

Spennn
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Second Moment of Area - semicircular "groove" in a beam?

Hi there guys, I've been looking into a problem that has been set as part of my Surf Science course (have your laughs I'm more than used to it! ;D) and not had much joy.

The problem that I have been having is that I can only find equations that relate to the second moment of area of I beams, Hollow cylinders etc. but, I am struggling to find anything relating to the shape that I need to investigate online or in books.

The shape I need to look at is a semicircle shaped groove in the surface of a beam.

So, I don't want to waste anybodies time, I'd just like to either know if I can relate someother shape to this or know if anybody can just point me in the right direction or let me know what I would call this shape so that I might have more luck searching myself :)

Thanks a bunch

Spen :)
 
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Welcome to PF!

Hi Spen! Welcome to PF! :smile:

Spennn said:
Hi there guys, I've been looking into a problem that has been set as part of my Surf Science course (have your laughs I'm more than used to it! ;D) …

No! sounds groovy! :wink:

(I'm not sure exactly what the shape is, but anyway …)

moment of area is additive, so you can find the moment of area of the groove, and then subtract that from the moment of area of the ungrooved beam. :smile:
 


Cheers buddy :)

Big help, now to get on with the coursework! meh!

Thanks again,

Spen
 
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