DETERMINING AREA WHEN THE FIELD OF VIEW IS KNOWN
A. Determine the diameter of the field of view for your microscope at low power: ________________mm (See: Determining the Field of View)
B. Using the following formula, determine the area of the field of view of your microscope-- AREA(MM2) = 3.14 X RADIUS2:
____________________mm2
SAMPLE:
MICROMASTER, MODEL 1175, HAS A FIELD OF VIEW DIAMETER OF 5MM AT LOW POWER. THEREFORE,
AREA = 3.14 X (2.5mm X 2.5 mm)
AREA = 3.14 X 6.25mm2
AREA = 19.625 mm2 = approximately 20mm2
Therefore, the Micromaster has a field of view area of ~20mm2.
C. Determine the diameter of the field of view at medium power- ________
and at high power- _____________. (Use the formula in “Determining the Field of View”.)
D. Determine the area of your field of view at medium power:
e. Determine the area your field of view at high power:
PROCEDURE:
1. ON A SHEET OF GRAPH PAPER, USE A COMPASS TO CREATE A CIRCLE WITH A RADIUS OF 5CM.
2. USE THE FORMULA FOR “AREA” TO DETERMINE THE AREA OF THE CIRCLE ON THE GRAPH PAPER. _________________CM2.
3. Look at a salt crystal using the low power objective of your microscope.
DRAW YOUR CHOSEN SALT CRYSTAL ONTO THE GRAPH PAPER AS ACCURATELY AS POSSIBLE. MAKE SURE TO REPRESENT BOTH THE LENGTH AND THE WIDTH.
4. FIND THE AREA OF YOUR DRAWING AFTER MEASURING THE LENGTH AND WIDTH OF YOUR DRAWN SALT CRYSTAL.
L = ____________, W = _________, A = _____________CM2
5. GO BACK TO THE SCOPE AND ESTIMATE THE LENGTH AND WIDTH OF THE CRYSTALTHAT YOU ORIGINALLY SELECTED.
LENGTH = ___________________ WIDTH = _____________________
CALCULATE THE AREA. _____________mm2
ENRICHMENT:
6. ON A SEPARATE SHEET OF GRAPH PAPER, CREATE THE CIRCLE AS BEFORE. WITHOUT USING THE SCOPE, DRAW THE CRYSTAL AT 10X POWER (MEDIUM POWER). REMEMBER, SIZE IS WHAT IS IMPORTANT IN THIS ACTIVITY, NOT DETAILS.
*LOOK AT THE SALT CRYSTAL UNDER MEDIUM POWER TO SEE HOW ACCURATELY YOU CREATED YOUR DRAWING.
7. REPEAT STEP 7, BUT DRAW THE SIZE OF THE SALT CRYSTAL AT HIGH POWER(40X).
*LOOK AT THE SALT CRYSTAL UNDER HIGH POWER TO SEE HOW ACCURATELY YOU CREATED YOUR DRAWING.