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Focal length, explained by RP Photonics Encyclopedia; focal distance, dioptric power, curved mirror, lens equation, microscope, photographic objective, focus, beam radius
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Thiery Legault - How to adjust the focal length ?
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The focal lengths of an objective lens and eyepiece are 192 cm and 8 cm respectively in a small telescope. Calculate its magnifying power and the separation between the two lenses.
How to Calculate Telescope Magnification
