Recent content by zicron

CB2=h2+(l-10)2 =h2+l2-20l+100 =(h2+l2)-20l+100 since sin2θ+cos2θ=1 =202-20l+100 =500-20l For triangle ABC , there is another unknown angle(ACB) and I will label as \thetaACB \frac{20}{sin(180-\theta)}=\frac{CB}{sin\theta}=\frac{10}{sin\theta_{ACB}} so by substituting CB =...

Well,there are only 2 things I know about this triangle which is AB = 10 cm and AC = 20 cm , all the rest are remain unknown.I try to solve it using trigonometry method such as A/sinA=B/sinB=C/sinC and theorem pythagoras but still I am stuck in this question. l is the length of the whole...

The incoming rays is parallel to the ray axis. According to the definition from the book : Rays that make small angle (such that sinθ≈θ ) with the mirror's axis are called paraxial rays.In the paraxial approximation only the paraxial rays are considered. The length of the curvature is the curve...

1. Find the length of the curvature of a concave mirror of 20cm that comply with paraxial approximation for all incident rays 2.conventional geometry formula , sinθ≈θ or tanθ≈θ for paraxial rays 3. I had try drafting out the diagram , labeling all the unknown angle with symbol and...

Thank you for the suggestion.I found the article I wanted , the library compiled it in a volume with a slightly different tittle.

I was trying to search an article on the internet the 'reference line' is "Atwater, M. A., and J. T. Ball, 1978: A numerical solar radiation model based on standard meteorological observations. Review paper. Solar Energy, 21, 163-170" However the most frustrating fact are the results return by...