Question

A converging lens is used to produce an image of an object on a screen. What change is needed for the image to be formed nearer to the lens ?

• A. Increase the focal length of the lens
• B. insert a diverging lens between the lens and the screen
• C. increase the distance of the object from the lens
• D. move the object closer to the lens.

Answer 1

Answer: (C)

increase the distance of the object from the lens

As the image is found on screen , therefore image is real i.e. object is placed beyond the focal length of converging lens .

Now , by lens equation

$v=\frac{-uf}{-u+f}$ (where $v$ must be +ive)

it is clear from this equation , that $v$ (distance of image from pole) will be smaller when we increase $u$ (distance of object from lens) .