Figure 3.7: A beetle larva as seen under a light microscope.
SOLUTION
Step 1: Calculate the total magnification
Use the same formula as above
overall magnification=power of eyepiece×power of objective
= 5× 10
= 50×the original size
Step 2: Now calculate the size of the object
If the image is 50 x larger than the object, what is the size of the object? Calculate this by
simple proportion given in the formula below.
Size =
size of image
overall magnification
=
20 mm
50
=0,4 mm
Worked example 3: Calculating actual size given of a structure given scale bar on an
image
QUESTION
Calculate the actual length of AB from the image shown in the micrograph given with the
scale bar given below.
Chapter 3. The basic units of life 69