MICROSCOPE CALCULATIONS A) Microscope Magnification = Ocular Lens X Objective Lens Ocular lens: 10x Low power objective: 4x Medium power objective: 10x High power objective: 40x What is the magnification under low power? What is the magnification under medium power? What is the magnification under high power ? B) Measuring Low Power Field Diameter (field of view ) : the distance from one side to the other under each power when looking through the microscope. Low power: use a ruler to measure it. Use this distance for High & Medium field diameter calculations as follows. Ex: low power field of view when measured with a ruler = 5 mm C) High & Medium field diameter must be calculated This formula is based upon the fact that the ratio of the diameters of the field of view is inversely proportional to the ratio of the magnifications. ie if the diameter doubles, the magnification is halved ie if the magnification doubles, the field diameter is halved Using the formula: Diameter of high power = magnification of low power Diameter of low power magnification of high power or D H = M L D L M H The diameter under high power = magnification of low X diameter of low mag high so, D H = M L x D L = 40 x X 5 mm = 0.5 mm so, the field diameter of high power is 0.5 mm M H 400 x Find the diameter of the field of view when using medium power. D m = M L D L M M /var/filecabinet/temp/converter_assets/3b/d5/3bd5f4709e92a77ae6370ecd3c912d911f38e42f.docx
You've reached the end of your free preview.
Want to read all 5 pages?
- Spring '10
- Trigraph, Eyepiece