Question

Your task in physics laboratory is to make a microscope from two lenses. one lens has a focal length of $2.0cm,$the other objective, and you want the eyepiece to be $16cm$from the objective.

(a). For viewing with a relaxed eye, how far should the sample be from the objective lens?

(b). What is the magnification of your microscope?

Short answer

(a). The sample should be $1.066cm$apart from the objective lens.

(b). The magnification of your microscope $M\approx 200$.

Step-by-step solution

Part(a) Step 1: Given information

We have given that:

The focal length of eye is$f_e=2.0cm$

the focal length of object is$f_o=1.0cm$

and the distance between eyepiece and object is $16cm$.

We need to find what is the magnification of your microscope.

Part (a) Step 2: Simplification

We use the formula,

$\frac{1}{f_o}=\frac{1}{S}+\frac{1}{d}$

$\frac{1}{1}-\frac{1}{16}=\frac{1}{S}$

$\frac{15}{16}=\frac{1}{S}$

$S=1.066cm$.

Here $S$is distance of sample from objective lens, $f_0$is the focal length of the object and $d$is the distance between lens and object.

part (b) step 1: Given Information

We need to find the magnification.

part (b) step 2: Calculation

For Magnification we can use:

$M=\frac{d}{S}\left(1+\frac{D}{f_e}\right)$

$M=\frac{16}{1.066}\left(1+\frac{25}{2}\right)$

$M\approx 200$.