Textbook of Engineering Drawing, Second Edition

4.24 Textbook of Enginnering Orawing------------------

I

A-+--~~+_~-~+_-~--B

F,

Fig. 4.35 Drawing asymptotes to a hyperbola

Rectangular Hyperbola

When the asymptotes to the hyperbola intersect each other at right angles, the curve is known as

a rectangular hyperbola.

Application of Conic Curves

An ellipsoid is generated by rotating an ellipse about its major axis. An ellipsoidal surface is used as

a head-lamp reflector. The light source (bulb) is placed at the fIrst focus F I (Fig.4.36). This works

effectively, if the second focus F2 is at a sufficient distance from the fIrst focus. Thus, the light

rays reflecting from the surface are almost parallel to each other.

Fig. 4.36 Ellipsoidal Reflector