Question

Lab Exercise 7 the other. Lay the ruler or a small cut piece of a ruler, whichever is available in the lab. The ruler will ha graduations in inches on one side and in centimeters and millimeters on the other. Lay ruler or piece of ruler flat on the stage with the metric side facing up. If it is a 6-inchal slide it under the mechanical stage clips so that the metric edge approximately bisch the condenser lens as seen through the stage. The field of view should look like the illustration below. (If you are unsure about how to proceed, see your lab instructor The illuminated half of the field of view The metric edge of the ruler passing through the middle of the field of view A millimeter mark of the ruler aligned with the left edge of the field of view The half of the field of view covered by the ruler rith the 4x objective in a field of view. Adjust the boue illustration. The distan With the 4x objective lens in place, look through the microscope and adjust the ruler so that it lays on a diameter of the field of view. Adjust the light so that the lines on the ruler are clearly visible. The field of view should look like the above illustration. The distance between the left edges of two adjacent lines is one millimeter. Place the left edge of any line at the left end of the diameter of the field (as you see it through the microscope), and measure the length of the diameter of field of view. It should be between 3 and 5 millimeters. Estimate the length to the nearest half of a millimeter and enter it on the blank below: Diameter of the field of view at 40x (low power): mm um Convert the diameter of field to micrometers (um): 2. Calculating the Diameter of the Field of View at Other Magnifications There is an inverse relationship between the total magnification and the diameter of the field of view -as magnification increases, the diameter of the field decreases in proportion. Thus, the diameter of field of view at any other magnification can be calculated mathematically according to the formula below: diameter of FOV at higher magnification y total magnification - diameter of FOV at higher power at lowest magnification y total magnification at lowest power On the left hand side of the equation, the diameter of FOV (field of view) at higher magnification that is to be determined this could be the diameter at total magnification 100X (i.e. objective lens #10) OR at magnification 400X (.e. objective lens #40) OR at magnification 1000X (i.e.objective lens #100). Always use the ruler measurement of

Answer 1

Diameter observed could be between 3 to 5 milli meter at 40 x magnification power

Hence diameter of field of view in 40 x is 4 mm

Convert diameter of field to micro meters - 0.004 micrometer