Images formed by Convex Lens

Question 1 Where should an object be placed in front of a convex lens so as to obtain image on same side of lens?

Question 2 The image formed by convex lens is seen to be real, inverted and diminished. What is the position of the object?

Question 3 The image formed by convex lens is seen to be real, inverted and highly magnified. What is the position of the object?

Image formation in Lenses using Ray Diagram

(1) A ray parallel to principal axis

A ray of light travelling parallel to principal axis passes or appears to pass through focus after passing through lens.

(2) A ray passing through principal focus

A ray of light passing through focus or directed towards it, travel parallel to principal axis after passing through the lens.

(3) A ray passing through optical centre of the lens

A ray passing through optical centre travels undeviated after passing through lens.

 

Images formed by Convex Lens

Object is at infinity

(1) Image is formed at second principal focus F₂

(2) It is diminished, real and inverted.

Object is beyond 2F₁

(2) It is diminished, real and inverted.

Object is at 2F₁

(1) Image is formed at 2F₂

(2) Image is of same size as that of object.

(3) It is real, inverted.

 

Object is between F₁ and 2F₁

(1) Image is formed beyond 2F₂

(2) It is larger in size than object.

(3) It is real, inverted.

Object is at F₁

(1) Image is formed at infinity.

(2) It is highly magnified, real, inverted.

Object is between F₁ and optical Centre of Lens

(1) Image is formed on same side of lens as that of object.

(2) It is larger in size than object.

(3) It is virtual and erect.