Microscope: magnification and focus sim
Total magnification is eyepiece magnification multiplied by objective magnification.
Microscope · magnification and focus · covers the GCSE, IGCSE, O-Level topic
What the sim shows
Total magnification is eyepiece magnification multiplied by objective magnification. Use the same 20 µm calibration specimen at each setting. The separate view represents a scaled image on paper: image size = actual size × magnification. Fine focus makes the outline clear; it does not change the calculated magnification. Start with the low-power objective.
- The round inset is a calibrated image, enlarged on screen for reading. Its paper scale spans 10 mm. The specimen is a calibration target with a known size.
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
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