Throughout the procedure alternative names for each of the o

Throughout the procedure, alternative names for each of the objective lenses were presented. Complete the following table by inserting the proper alternative names with the appropriate objective lens. Also, determine the total magnification when using each of the objective lenses with a 10 times ocular lens. A special filter has been added to the lamp of your compound light microscope that allows only light of wavelength 495 nm to pass through. What is the best resolution that could be obtained using this filler and the standard light microscope? (Note best numerical aperture in light microscopy is 1.25) You are observing a classmate attempt to view a specimen at 1000 times total magnification. The student began with the stage raised and attempted to start out using the 100 times objective lens. The student then moved back to the 40 times objective, but still could not view the specimen, even at this lower magnification Help your classmate by making several suggestions as to how this work should have been attempted. making sure to point out any problems with the technique that you observed.

Solution

Answer 1 :

since the eye lens magnification is fixed at 10x and the total magnification is given by the power of objective lens x power of eye lens, therefore the table could be completed as :

answer 2: the formula for resolution is given as : resolution = 0.61 x wavelength / Numerical aperture

since the wavelength is 495 nm the resolution would be : 0.61 x 495 x 10^-9 / 1.25

= 2.41 micrometers

this is the best resolution that we can get using this combination.

Answer 3: the suggestions that we could make are:

We should always start from the lowest power of the objective lens that is 4x, so that the total magnification is less and we could focus gradually into higher powers. If we start with a higher power it would be very difficult to adjust the slide into the focus to see the specific part that we want to see. also, at higher powers, like 1000x, when we use a 100x objective lens, we need to use oil to properly visualise the slide, therfore we should always start with a 4x objective lens then 10x , then 40x and finally 100x.

common name of objective lens	objective lens magnification	ocular lens magnification	total magnification
scanning	4x	10x	40 x
low power	10x	10x	100x
high power	40x	10x	400x
oil immersion	100x	10x	1000 x