Conic Sections Question 70
Question: The locus of a foot of perpendicular drawn to the tangent of parabola $ y^{2}=4ax $ from focus, is
[RPET 1989]
Options:
A) $ x=0 $
B) $ y=0 $
C) $ y^{2}=2a(x+a) $
D) $ x^{2}+y^{2}(x+a)=0 $
Show Answer
Answer:
Correct Answer: A
Solution:
Tangent to parabola is, $ y=mx+\frac{a}{m} $ …..(i) A line perpendicular to tangent and passing from focus $ (a,0) $ is, $ y=-\frac{x}{m}+\frac{a}{m} $ ……(ii) Solving both lines (i) and (ii)
therefore $ x=0 $ .