Which of the following relations about the focal length fo of the objective and focal length fe of the eye piece of a compound is correct?

Which of the following relations about the focal length f_o of the objective and focal length f_e of the eye piece of a compound is correct?

Answer Details

A compound microscope is an optical instrument that uses two lenses (the objective lens and the eyepiece lens) to produce magnified images of small objects. The objective lens forms a real image of the object that is located inside the focal point of the eyepiece. The eyepiece lens then acts as a magnifying glass to produce a virtual image of the real image formed by the objective lens. The magnification produced by the compound microscope is the product of the magnification produced by each lens. The formula for calculating the magnification of a compound microscope is given as: M = - (f_o / f_e) Where M is the magnification produced by the microscope, f_o is the focal length of the objective lens, and f_e is the focal length of the eyepiece lens. From the formula, we can see that the focal length of the objective lens and the focal length of the eyepiece lens are inversely proportional to the magnification produced by the microscope. As the magnification of the microscope increases, the focal length of the objective lens decreases, and the focal length of the eyepiece lens increases. Therefore, the correct relation between the focal length of the objective lens and the focal length of the eyepiece lens is: f_o < f_e This is because the objective lens is designed to produce a real image of the object, and the eyepiece lens is designed to magnify that image. To achieve a higher magnification, the eyepiece lens must have a shorter focal length than the objective lens.