Q24.A convex lens of focal length 20 cm produces images of the same magnification 2 when an object is kept at two distances x1 and x2(x1 > x2) from the lens. The ratio of x1 and x2 is: (1) 2 : 1 (2) 5 : 3 (3) 4 : 3 (4) 3 : 1
What This Question Tests
This question requires solving the lens formula and magnification equation for a convex lens, recognizing that a specific magnification magnitude can be achieved for both real and virtual images, leading to two distinct object distances.
Concepts Tested
Formulas Used
1/f = 1/v - 1/u
m = v/u
📚 NCERT Sections This Tests
9.19 — A Screen Is Placed 90Cm From An Object. The Image Of The Object On
Physics Class 12 · Chapter 9
9.19 A screen is placed 90cm from an object. The image of the object on the screen is formed by a convex lens at two different locations separated by 20cm. Determine the focal length of the lens.
9.7 — Double-Convex Lenses Are To Be Manufactured From A Glass Of
Physics Class 12 · Chapter 9
9.7 Double-convex lenses are to be manufactured from a glass of refractive index 1.55, with both faces of the same radius of curvature. What is the radius of curvature required if the focal length is to be 20cm?
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?
📋 Question Details
- Chapter
- Ray Optics
- Topic
- Lenses and Magnification
- Year
- 2019
- Shift
- 09 Apr Shift 2
- Q Number
- Q24
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 9: Ray Optics and Optical Instruments
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