Question

ocular power = 10x
low power objective = 20x
high power objective = 50x
a) what is the highest magnification you could get using this microscope?
b) if the diameter of the low power field is 2 mm, what is the diameter of the high power field of view in mm? in micrometers?
c) if 10 cells can fit end to end in the low power field of view, how many of those cells would you see under high power?

Explanation:

Step1: Calculate highest magnification

Multiply ocular power by high - power objective.
$10\times50 = 500$

Step2: Calculate diameter of high - power field in mm

Use inverse relationship of magnification and field diameter. Magnification ratio is $\frac{50}{20}$. So diameter of high - power field in mm is $2\times\frac{20}{50}=0.8$ mm.

Step3: Convert diameter to micrometers

Since $1$ mm = $1000$ micrometers, $0.8$ mm is $0.8\times1000 = 800$ micrometers.

Step4: Calculate number of cells under high - power

Use inverse relationship of magnification and number of cells. Number of cells under high - power is $10\times\frac{20}{50}=4$

Answer:

a) 500
b) 0.8 mm, 800 micrometers
c) 4