An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed.

Q. 10 : – An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed. 

 

Answer:-

Height of the object h = + 5 cm
Focal length f = + 10 cm
object-distance u = –25 cm
Image-distance v = ?
Height of the image h′ = ?

Q10-Light–Reflection-and-Refraction-Science-CBSE-Class-10

 

1 1 1


=
v u f
=> 1 1 1

=

v 10 25
=> 5 − 2 3
=
=
50 50
=> 50
v =
= 16.66 cm
3

A real and inverted image will be formed on other side of lense at 16.66 cm from its optical centre

=> v
m =
u
=> h2 16.66

=
h1 − 25
=> h2 16.66

=
5 − 25
=> −16.66 × 5
h2 =
25
=>
h2 = − 3.33 cm

An inverted, 3.33 cm high image will be formed.