# I am doing my science 10 by correspondence and I came upon a question that puzzles me. Why are modern light microscopes called Compound microscopes. That and How would I "determine theactual size of the cells shown in the illistration if the field diameter measures 2.2 mm"??? I need help!!!!

Compound microscopes have two lenses, separated from each other. One lens is called the objective and the other is called the eyepice. Magnifying lenses have one lens.

For your second question, estimate or measure the ratio of the diameter of your object, as seen though the eyepiece, to the size of the field of view. Some microsopes have a calibrated scale to help you do this. Multiply that ratio by the field of view diameter (2.2 mm). The field of view may change as you change lenses, so make sure that it really is 2.2 mm. It may be something else.

## Modern light microscopes are called compound microscopes because they use a system of multiple lenses to magnify the image of the specimen being observed. These microscopes have two lenses separated from each other - the objective lens and the eyepiece lens. The compound microscope design allows for higher magnification and resolution compared to a single lens magnifying microscope.

To determine the actual size of cells shown in the illustration when the field diameter measures 2.2 mm, you can use the following steps:

1. Estimate or measure the ratio of the diameter of the object you're observing, as seen through the eyepiece, to the size of the field of view.
2. Some microscopes may have a calibrated scale that helps in determining this ratio, but if not, you can estimate it by comparing the size of the object to the size of the field of view.
3. Multiply this ratio by the field of view diameter (given as 2.2 mm in your case). This will give you an approximation of the actual size of the cells.

It's important to note that the field of view diameter may change as you change lenses on the microscope. So, make sure to verify that the field of view is indeed 2.2 mm for the specific lens you're using.