Physics 2014 JAMB Past Questions - Question 31: In a compound microscope ,the objective and the eyepiece focal length are

Correct Answer

B

Explanation

A compound microscope consist of two convex lenses. of short focal lengths.In a compound microscope, the objective and eyepiece have specific focal lengths that are chosen to optimize the performance of the microscope. The objective lens is the lens closest to the object being observed, and its primary function is to collect and magnify the light coming from the specimen. The eyepiece lens, on the other hand, is the lens closest to your eye and further magnifies the image formed by the objective.

The objective lens typically has a shorter focal length, usually on the order of a few millimeters, which allows it to collect a large amount of light and create a real, inverted image of the specimen. The objective lens provides the primary magnification in the microscope.

The eyepiece lens has a longer focal length, typically on the order of a few centimeters. Its role is to further magnify the real image produced by the objective and to allow your eye to comfortably view it. The eyepiece is responsible for the secondary magnification in the microscope.

The combination of the objective and eyepiece focal lengths, along with the tube length (the distance between the two lenses), determines the overall magnification of the compound microscope. The magnification of a compound microscope is typically calculated as the product of the objective magnification and the eyepiece magnification.

The specific focal lengths of the objective and eyepiece lenses can vary depending on the design and intended use of the microscope, but the relationship between the two focal lengths is essential for achieving the desired magnification and image quality.