Q15.The position of the image formed by the combination of lenses is : (1) 15 cm (right of second lens) (2) 30 cm (left of third lens) (3) 15 cm (left of second lens) (4) 30 cm (right of third lens)
What This Question Tests
This is a multi-step problem that requires sequential application of the lens formula for each lens in the combination, where the image formed by one lens acts as the object for the next.
Concepts Tested
Formulas Used
1/f = 1/v - 1/u
📚 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?
9.20 — (A) Determine The ‘Effective Focal Length’ Of The Combination Of
Physics Class 12 · Chapter 9
9.20 (a) Determine the ‘effective focal length’ of the combination of the two lenses in Exercise 9.10, if they are placed 8.0cm apart with their principal axes coincident. Does the answer depend on which side of the combination a beam of parallel light is incident? Is the notion of effective focal length of this system useful at all? (b) An object 1.5 cm in size is placed on the side of the convex lens in the arrangement (a) above. The distance between the object and the convex lens is 40 cm. Determine the magnification produced by the two-lens system, and the size of the image.
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.
📋 Question Details
- Chapter
- Ray Optics
- Topic
- Lens combination
- Year
- 2024
- Shift
- 08 Apr Shift 2
- Q Number
- Q15
- Type
- Multi concept
- NCERT Ref
- Class 12 Physics Ch 9: Ray Optics and Optical Instruments
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