Why, under a microscope, is magnification the length and width of an object? Not area, volume Under a microscope, what is magnified is length or width. Why not area or volume?

Why, under a microscope, is magnification the length and width of an object? Not area, volume Under a microscope, what is magnified is length or width. Why not area or volume?

Let me give you a simple example. If you see a rectangle (length a, width b) in the field of vision of a microscope, suppose that the original total magnification is 100 times (objective lens magnification multiplied by eyepiece magnification), now you can change the total magnification to 200 times by adjusting the objective lens. Compared with the original, the magnification is 2 times, The "2 times" here means that the length of the observed rectangle becomes 2a, and the width also becomes 2B. The "2 times" here is the multiple of linear method (also the multiple of one-dimensional method, which is conventionally easy to understand. The "magnification" in the microscope refers to this multiple). At this time, you can easily get that the area of the rectangle is 4AB by calculation, 4 times the area of the rectangle in the original field of vision