1. OER- Engineering Drawing Topic: Introduction to Conic Sections
IITBombayX: FDP201x Pedagogy for Online and Blended Teaching-Learning Process
OER- Engineering Drawing
(Mechanical & Allied)
Topic: Introduction to Conic Sections
Team Details:
Prof. Sunil Pipleya (Team Leader)
Prof. Sumit Chandak (Team Member 1)
Dr. Rakesh Kumar Malviya (Team Member 2)

2. ENGINEERING CURVES
Conic Sections
Ellipse
Parabola
Hyperbola

3. β α β α β< α β> α α β β= α CONIC SECTIONS
ELLIPSE, PARABOLA AND HYPERBOLA ARE CALLED CONIC SECTIONS
BECAUSE
THESE CURVES APPEAR ON THE SURFACE OF A CONE
WHEN IT IS CUT BY SOME TYPICAL CUTTING PLANES.
OBSERVE
ILLUSTRATIONS
GIVEN BELOW..
Ellipse
e<1 β α α β
β< α
β> α
Section Plane
Through all the Generators
Section Plane
Inclined at an angle
Greater than that
of end generator.
Hyperbola
e>1 α β
β= α
Parabola
Section Plane Parallel
to end generator.
e=1

4. Terminology

5. What is eccentricity ?
Conic section
Directrix A P N
Axis C D V F
Focus
Vertex B
Distance from focus PF VF
eccentricity = = =
Distance from directrix PN VC

6. SECOND DEFINATION OF AN ELLIPSE:-
These are the loci of points moving in a plane such that the ratio of it’s distances
from a fixed point And a fixed line always remains constant.
The Ratio is called ECCENTRICITY. (E)
For Ellipse E<1
For Parabola E=1
For Hyperbola E>1
SECOND DEFINATION OF AN ELLIPSE:-
It is a locus of a point moving in a plane
such that the SUM of it’s distances from TWO fixed points
always remains constant.
{And this sum equals to the length of major axis.}
These TWO fixed points are FOCUS 1 & FOCUS 2
COMMON DEFINATION OF ELLIPSE, PARABOLA & HYPERBOLA:

7. SECOND DEFINATION OF AN ELLIPSE:- B F1 F2
AB: Major Axis D
CD: Minor Axis
PF1+PF2=Constant=AB= Major Axis
SECOND DEFINATION OF AN ELLIPSE:-
It is a locus of a point moving in a plane
such that the SUM of it’s distances from TWO fixed points
always remains constant.
{And this sum equals to the length of major axis.}
These TWO fixed points are FOCUS 1 & FOCUS 2

8. Thank You