Question

A 2.26 cm tall object is placed in 18.6 cm in front of a convex lens. The focal length

Answer 1

Answer:

the image is -38.7 cm from the lens

Explanation:

We use the lens equation which says  

$\frac{1}{u}+\frac{1}{v}=\frac{1}{f}$

where $u$ is the distance to the object, $v$ is the distance to the image, and $f$  is the focal length.

Now, in our case

$u =18.6cm$,

$v= 35.8cm$,

$f = 35.8cm$;

therefore,

$\frac{1}{18.6}+\frac{1}{v}=\frac{1}{35.8}$

$\frac{1}{v}=\frac{1}{35.8}-\frac{1}{18.6}$

$\boxed{v=-38.7cm}$

where the negative sign indicates that the image is virtual and on the same side of the lens as the object.