Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Sample Paper>Q 67

HARD

12th CBSE

IMPORTANT

Earn 100

Show that the least possible distance between an object and its real image in a convex lens is $4 f$ , where $f$ is the focal length of the lens.

Important Questions on Ray Optics and Optical Instruments

HARD

12th CBSE

IMPORTANT

Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Sample Paper>Q 68

In an astronomical telescope in normal adjustment, a straight black line of length

L

is drawn on the objective lens. The eyepiece forms a real image of this line whose length is

l

. What is the angular magnification of the telescope?

HARD

12th CBSE

IMPORTANT

Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Sample Paper>Q 70

Draw a ray diagram for the formation of image of a point object by a thin double convex lens having radii of curvature

R_{1}

and

R_{2}

. Hence derive lens maker’s formula.

HARD

12th CBSE

IMPORTANT

Physics Crash Course (Based on Revised Syllabus-2023)>Chapter 9 - Ray Optics and Optical Instruments>Sample Paper>Q 71

A converging lens has a focal length of

10 cm

in air. It is made of a material of refractive index

1.6 .

If it is immersed in a liquid of refractive index

1.3,

find its new focal length.