Q70.Consider a circle C1 : x 2 + y2 – 4x – 2y = α – 5. Let its mirror image in the line y = 2x + 1 be another circle C2 : 5x2 + 5y2 –10fx – 10gy + 36 = 0. Let r be the radius of C2 . Then α + r is equal to ________
What This Question Tests
This question combines the concepts of finding the center and radius of a circle with determining the mirror image of a point (center) in a given line to find properties of the reflected circle.
Concepts Tested
Formulas Used
(x-h)² + (y-k)² = r²
Reflection formulas for a point about a line
📚 NCERT Sections This Tests
5.11 — Draw All The Isomers (Geometrical And Optical) Of:
Chemistry Class 11 · Chapter 5
5.11 Draw all the isomers (geometrical and optical) of: (i) [CoCl2(en)2] + (ii) [Co(NH3)Cl(en)2] 2+ (iii) [Co(NH3)2Cl2(en)]+
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
- Circles
- Topic
- Circle and Mirror Image
- Year
- 2023
- Shift
- 08 Apr Shift 1
- Q Number
- Q70
- Type
- Numerical
- NCERT Ref
- Class 11 Mathematics Ch 11: Conic Sections (Basic Circle properties), Class 11 Mathematics Ch 10: Straight Lines (Reflection)
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