Question

How far from the lens must the film in a camera be, if the lens has a 35.0 mm focal length and is being used to photograph a flower 75.0 cm away? Explicitly show how you follow the steps in the Problem–Solving Strategy for lenses.

Answer 1

Answer:

The film in a camera be is placed at a distance of 3.67 cm.

Explanation:

Given that,

Focal length of the lens, f = +35 mm = +3.5 cm

Object distance of the flower, u = -75 cm

Using lens formula to find the distance from the lens must the film in a camera be. Using lens formula as :

$\dfrac{1}{v}-\dfrac{1}{u}=\dfrac{1}{f}\\\\\dfrac{1}{v}=\dfrac{1}{f}+\dfrac{1}{u}\\\\\dfrac{1}{v}=\dfrac{1}{(3.5)}+\dfrac{1}{(-75)}\\\\v=3.67\ cm$

So, the film in a camera be is placed at a distance of 3.67 cm.