WINTER 2019 VARIANT 12

Q1:
A student calibrated the scale on an eyepiece graticule in the eyepiece lens of a light microscope. The student was given a stage micrometer scale to use. The divisions on the stage micrometer scale were 0.1 mm apart. Which data must the student collect in order to calibrate the eyepiece graticule?

 1 magnification of the eyepiece lens of the microscope
 2 number of divisions of the stage micrometer scale seen in one field of view of the microscope
 3 number of divisions of the eyepiece graticule scale equivalent to each division of the stage micrometer      scale

 A 1 and 3
 B 2 and 3
 C 2 only
 D 3 only


In this question, magnification of the eyepiece lens of the microscope is of no help to the calibration of the eyepiece graticule since it is the objective lens for which the eyepiece graticule has to be calibrated seperately. The eyepiece magnification is usually fixed Also, it is the eyepiece divisions that are to be calibrated, not the stage micrometer. We just need to check how many divisions of an eyepiece graticule correspond to one division of the stage micrometer which in this case is equal to 0.1mm. Then apply the cross multiplication method to find the calibration of one division of the eyepiece graticule.

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