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| Compound Microscope |
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| A Laboratory Model of Compound Microscope |
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| It is an optical instrument used for observing highly magnified images of tiny objects. |
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| O - Objective |
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| E - Eyepiece |
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| D - Distance of distinct vision |
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| AB - Object |
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| A'B' - First image |
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| A"B" - Final image |
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| O1,O2 - are optic centers of O and E |
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| O, FO - Focal length of objective |
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| O, Fe - Focal length of eyepiece |
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| Magnifying power of compound microscope is defined as the ratio of the angle subtended at the eye by the final image to the angle subtended at the eye by the object, when both the final image and the object are situated at the least distance of distant vision from the eye. |
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| m = magnification produced x magnification produced due to eye lens due to objective lens |
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| m = me x mo |
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| (-ve sign shows that final image is inverted with respect to the object) |
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| Note: If the object is very close to fo, the focus of lens O then |
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| and as AlBl is very close to the eye lens |
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| Vo = OlBl O1O2 = L = length of tube |
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| If fo and fe both are small then magnifying power will be large. |
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