Microscope calculations - MissHaynes-Science

1 Page 1 of 12 Microscope calculations 1. Converting between units You only need to remember two sums to convert between any units. Basic conversions Complete the table below Example 1 Example 2 Convert 2350nm Convert 143mm 2350nm 1000 = m 143mm x 1000 = 143,000 m m 1000 = 143,000 m x 1000 = 143,000,000nm Millimetre Micrometre Nanometre 1580 174 3 18 23 8 5 Page 2 of 12 2. The equation triangle This equation triangle gives you 3 equations. What are they? Image = Actual = Magnification = Basic calculations 1. A human hair is 25 m and is observed at x400. a) Calculate the size of the image in m. b) Calculate the size of this image in mm.

2 2. A bacterial cell is drawn 1000mm long. It was viewed at a magnification of x500. a) Calculate the size of the bacteria in mm. b) Calculate the size of the bacteria in m. 3. A mitochondria was drawn 20mm long. Its actual size is 2 m. a) Calculate the size of the image in m b) Calculate the magnification used. Page 3 of 12 magnification. Equation needed to calculate Magnification = Questions Page 4 of 12 actual size measure the scale bar Equation needed to calculate Actual size = Questions Page 5 of 12 Page 6 of 12 5. Calculating actual size use the scale bar to calculate magnification first Equations needed - Magnification = Actual size = Page 7 of 12 Page 8 of 12 6.

3 In context animal cell For questions 2-5 calculate the answers in m N/A Nucleolus N/A N/A Page 9 of 12 In context plant cell For uestions 2-5 calculate the answers in m N/A N/A I _____ Page 10 of 12 7. Using micrographs Page 11 of 12 Exam questions standard demand The image below shows part of a root from a cress plant. (a) What type of Microscope was used to create the image above? _____ (1) (b) The magnification of the cress root in the image above is 210. There are 1000 micrometres ( m) in a millimetre (mm). Calculate the real length of the root hair, X. Give your answer in micrometres ( m). _____ _____ _____ _____ Real length X = _____ m (2) (Total 3 marks)X 210 Page 12 of 12 Evaluation Did you always show your workings clearly?

4 Did you always get the conversions between units right? Did you make accurate measurements from diagrams? Did you forget steps in calculations ? Did you use the wrong equation to answer a question? Did you make notes/annotate the question? What could you do to improve? Watch videos on calculations ? Do more practice questions? How and when will you do this? Always / Sometimes / Never Always / Sometimes / Never Always / Sometimes / Never Always / Sometimes / Never Always / Sometimes / Never Always / Sometimes / Never