wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

If p be the perpendicular distance of a focal chord PQ of length l from the vertex A of the parabola y2=4ax, then l varies inversely as

A
p2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
1p2
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
p
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
1p
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is B 1p2
PQ is focal chord
l=a(t+1t)2
Also chord equation joining points t1,t2 is
y(t1+t2)2x2at1t2=0
PQ is focal chord
y(t1t)2x+2a=0
p=2a(t1t)2+4
p2=4a2(t+1t)2
Clearly, lp2=4a3(constant)

flag
Suggest Corrections
thumbs-up
7
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Parabola
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon