Q95.The equation of a tangent to the parabola y2 = 8x is y = x + 2 . The point on this line from which the other tangent to the parabola is perpendicular to the given tangent is (1) (โ1, 1) (2) (0, 2) (3) (2, 4) (4) (โ2, 0) y2 x2
What This Question Tests
This question tests a key property of parabolas: the intersection point of two perpendicular tangents lies on the directrix. It requires identifying the directrix and then finding its intersection with the given tangent line.
Concepts Tested
Formulas Used
Equation of tangent to y^2=4ax: y=mx+a/m
Directrix of y^2=4ax: x=-a
Condition for perpendicular lines: m1*m2 = -1
๐ NCERT Sections This Tests
9.8 โ A Beam Of Light Converges At A Point P. Now A Lens Is Placed In The
Physics Class 12 ยท Chapter 9
9.8 A beam of light converges at a point P. Now a lens is placed in the path of the convergent beam 12cm from P. At what point does the beam converge if the lens is (a) a convex lens of focal length 20cm, and (b) a concave lens of focal length 16cm?
9.15 โ Apply Mirror Equation And The Condition:
Physics Class 12 ยท Chapter 9
9.15 Apply mirror equation and the condition: (a) f < 0 (concave mirror); u < 0 (object on left) (b) f > 0; u < 0 (c) f > 0 (convex mirror) and u < 0 (d) f < 0 (concave mirror); f < u < 0 to deduce the desired result.
2.1 โ Two Charges 5 ร 10โ8 C And โ3 ร 10โ8 C Are Located 16 Cm Apart. At
Physics Class 11 ยท Chapter 2
2.1 Two charges 5 ร 10โ8 C and โ3 ร 10โ8 C are located 16 cm apart. At what point(s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero.
๐ Question Details
- Chapter
- Parabola
- Topic
- Tangents to Parabola, Directrix
- Year
- 2007
- Shift
- Unknown
- Q Number
- Q95
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 11: Conic Sections
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