This problem refers specifically to http://books.google.com/books?id=W9...ss components on an arbitrary plane"&f=false".(adsbygoogle = window.adsbygoogle || []).push({});

The text comments that Area BOC = Projection of area ABC on the yz plane, and that this equals the area of ABC times the direction cosine in the x-direction of the normal vector to the plane, and so on for the other faces.

Similarly, http://books.google.com/books?id=Gl...ss components on an arbitrary plane"&f=false" states that "it can be seen" that the ratio of areas A_{x}/A = n_{x}, etc.

I'm looking for a mathematical verification that this is true. Most likely because it is a math issue, the authors deemed the explanation unecessary in a solid mechanics text. My linear algebra background is pretty weak, so you may need to include some fundamentals in order for me to follow.

Thanks in advance.

**Physics Forums | Science Articles, Homework Help, Discussion**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Projection of area onto a plane

**Physics Forums | Science Articles, Homework Help, Discussion**