Question

Match the columns by referring to the definition given below.

"A conic is the locus of a point which moves in a plane so that its distance from a fixed point is in a constant ratio to its perpendicular distance from a fixed straight line”.

$\begin{array}{cc}\text{Definition}& \text{Name}\\ \text{P) Fixed point}& \text{1. Axis}\\ \text{Q) Fixed straight line}& \text{2. Vertex}\\ \text{R) Constant ratio}& \text{3. Directrix}\\ \text{S) Line passing through fixed point and perpendicular to fixed line}& \text{4. Focus}\\ & \text{5. Eccentricity}\end{array}$

• A. $P-4,Q-3,R-1,S-5$
• B. $P-3,Q-4,R-5,S-1$
• C. $P-4,Q-3,R-5,S-1$
• D. $P-4,Q-3,R-5,S-2$

Answer 1

The correct option is C

$P-4,Q-3,R-5,S-1$

The fixed point in the definition is S and the fixed line is L which are known as focus and directrix respectively.

P is our moving point .
PM is the perpendicular distance from directrix(L).

The constant ratio $\frac{PS}{PM}$ is called the eccentricity (e).

From S,we can draw a line perpendicular to directrix.This line is called axis.

Hence, the correct answer is Option c.