Q65.The length of the latus rectum of a parabola, whose vertex and focus are on the positive x-axis at a distance R and S(> R) respectively from the origin, is : (1) 2( S −R) (2) 2(S + R) (3) 4(S −R) (4) 4(S + R)
What This Question Tests
This question directly applies the definition of the latus rectum of a parabola and the relationship between vertex, focus, and the parameter 'a'.
Concepts Tested
Formulas Used
Length of latus rectum = 4a
Distance between vertex and focus = a
📚 NCERT Sections This Tests
9.8 — A Beam Of Light Converges At A Point P. Now A Lens Is Placed In The
Physics Class 12 · 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 — Apply Mirror Equation And The Condition:
Physics Class 12 · 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.
9.1 — A Small Candle, 2.5 Cm In Size Is Placed At 27 Cm In Front Of A Concave
Physics Class 12 · Chapter 9
9.1 A small candle, 2.5 cm in size is placed at 27 cm in front of a concave mirror of radius of curvature 36 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? Describe the nature and size of the image. If the candle is moved closer to the mirror, how would the screen have to be moved?
📋 Question Details
- Chapter
- Parabola
- Topic
- Latus rectum of a parabola
- Year
- 2021
- Shift
- 31 Aug Shift 1
- Q Number
- Q65
- Type
- MCQ
- NCERT Ref
- Class 11 Mathematics Ch 11: Conic Sections
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