Mrs. Deringer - The Microscope

How to Compute Magnification.


The part of the microscope that you look through is called the eyepiece. If you look on the ring on the eyepiece you will see 10X, this is because the eyepiece magnifies the specimen ten times

The specimen is also magnified a second time by the objective lenses on the nosepiece.

There are usually three objective lenses

1. Scanning Lens magnifies the specimen 4 times (4X)

2. Low power objective magnifies the specimen 10 times (10X)

3. High power objective lens magnifies the specimen 40 or 43 times (40X) or (43X)

Therefore, when you are computing the total magnification of a specimen you must multiply the objective lens times the eyepiece. The eyepiece magnification is usually 10 x.The objective lenses are usually 4x, 10x, and 43x

For example: Using the high-power objective lens of (43x), with an eyepiece of a 10x, the magnification would be 430x. That means that the specimen is being magnified 430 times its original size.

Click Here to watch a movie on how to compute magnification.

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