Passage IV

The total magnification provided by a compound light microscope is determined by multiplying the power (magnification) of the ocular lens (eyepiece) by the power of the objective lens. The area seen when looking through a microscope is called the field of view (FOV). The diameter of the FOV varies with total magnification. Table 1 gives the power of, and the FOV diameter associated with, 4 different objective lenses on a microscope (Microscope M) with an ocular lens power of 10x. Table 2 lists 4 types of microscopic organisms found in pond water and gives their size ranges and their distinguishing characteristics.

22. A student needs to examine an object through Microscope M using a total magnification of 400x. Based on Table 1, which objective lens should the student use?

Answer and Explanation

Your Answer is

Correct Answer is H

Explanation

Look at the first sentence of the article total magnification=power of ocular lens×power of objective lens. The penultimate third line of the article also gives the power of the ocular lens is 10×, so when the total magnification is 400×, the objective lens The power should be 40×, compared to table 1, it should be Lens 3