Explain5 marksChallenge
A student examines a photomicrograph of a plant cell taken using a light microscope. The photomicrograph includes a scale bar labelled '10 µm'. The student measures the length of the scale bar on the print as 20 mm. The length of the cell on the print is 80 mm.
Explain how the student can use the scale bar to determine the actual length of the cell. In your answer, define magnification and resolution, and explain why increasing the magnification beyond the resolution limit of the light microscope does not improve the image quality.