# Hyperbolic Issues

I shouldn’t be writing this post as I have few other things to tend to. Anyway, I was watching the TedX video on what’s so sexy about Math? and in the comments section someone had asked a cute question whether a straight line can pass through a curved surface? The answer is the famous hyperbolic slot. Those who don’t want to see how, the answer is yes, a straight line can pass through a curved surface. The hyperbola reminded me of parabola that in turn reminded me of parabola powered calculator that I saw in exploratorium – a science museum in SF bay area. The interesting tool is used to multiply two numbers. I am pasting a photograph that I took months ago here; the tool is not only easy to use but self explanatory.

The two points where the parabola and the string intersect are the two numbers whose product we wish to find. The point where the string touches the axis of the symmetry (vertical line passing through the vertex) is the value of the product of those two numbers.

I came across the conic sections i.e. ellipse, parabola and hyperbola in my class 11; I could gauge ellipse and parabola for I had seen the practical use of the two shapes but I could never imagine what on earth is this hyperbola. First of all, it has two curves and I never understood how can any object follow such a path. Too bad that no one showed the hyperbolic slot to us and internet  wasn’t as prevalent in those days( 2004) as it is now. One can learn anything on YouTube these days.

Anyway, few days ago I factory reset my Nexus 6P and checked all applications for the consistency. I opened the camera and took the photograph of my desk and wall.

And here was the hyperbola. The lamp shade’s shadow formed a hyperbolic curve on the wall.