Q30.In an experiment to measure the focal length ( ๐) of a convex lens, the magnitude of object distance ( ๐ฅ) and the image distance ( ๐ฆ) are measured with reference to the focal point of the lens. The ๐ฆ- ๐ฅ plot is shown in figure. The focal length of the lens is _____cm .
What This Question Tests
This question tests the ability to interpret a y-x plot from an experiment involving a convex lens and apply Newton's form of the lens formula to find the focal length.
Concepts Tested
Formulas Used
xy = f^2 (Newton's lens formula)
๐ NCERT Sections This Tests
9.19 โ A Screen Is Placed 90Cm From An Object. The Image Of The Object On
Physics Class 12 ยท 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 โ Double-Convex Lenses Are To Be Manufactured From A Glass Of
Physics Class 12 ยท 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 โ A Beam Of Light Converges At A Point P. Now A Lens Is Placed In The
Physics Class 12 ยท 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?
๐ Question Details
- Chapter
- Ray Optics
- Topic
- Lens formula (Newton's form)
- Year
- 2024
- Shift
- 30 Jan Shift 2
- Q Number
- Q30
- Type
- Graph based
- NCERT Ref
- Class 12 Physics Ch 9: Ray Optics and Optical Instruments
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