Q17.A convex lens of focal length 40 cm forms an image of an extended source of light on a photoelectric cell. A current I is produced. The lens is replaced by another convex lens having the same diameter but focal length 20 cm. The photoelectric current now is (1) I (2) 4I 2 (3) 2I (4) I
What This Question Tests
This question requires applying the formula for the refractive index of a prism in terms of the angle of prism and minimum deviation, followed by trigonometric manipulation.
Concepts Tested
Formulas Used
Ξ = sin((A + Îīm)/2) / sin(A/2)
ð NCERT Sections This Tests
9.8 â 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?
9.19 â 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 â 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?
ð Question Details
- Chapter
- Ray Optics
- Topic
- Minimum deviation of prism
- Year
- 2024
- Shift
- 27 Jan Shift 1
- Q Number
- Q17
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 9: Ray Optics and Optical Instruments
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