Question

Lab Exercise 7 5. Place the s PROCEDURE (letter "e" prepared slide) the equation on the lens is in place 1. Record the details from the objective lenses and the ocular lens. Use the ea previous page to determine the total magnification when each objective len and enter the results in the table below: power (40 will come will, do no if necessar the course Your micro lens to anc Reposition Magnification of ocular lens lens Total magnificati Stripe color of objective lens Power low Magnification of objective lens - tray. Answ a. In gene middle high drys low po or doe: • size oil immersion • widt • resol • light 2. With the low power (4x) objective lens in place, observe the letter "e" through the microscope. Use the coarse adjustment knob to bring the stage all the way up, then slot move it back down until the letter "e" comes into focus. Then use the mechanical stage control knobs to place the letter "e" in the center of the field of view. Sharpen the focus if necessary, with the fine adjustment knob. Adjust the iris diaphragm lever to maximize contrast. Under low power, this is usually done by closing the iris diaphragm, which minimizes the amount of light. 3. Answer the following questions before continuing on to step 4: a. How is the letter "e" oriented (right side up or upside down) relative to the unaided eye? . obje b. How c b. Which way does the image move when tthe slide is moved to the right or left? c. Which way does the image move when the slide is moved forward or backward? d. Does the letter "e" appear to be larger than it was to the unaided eye? c. Comp (40x) | Pow Lo e. If the image of the specimen created by the lens system appears larger, does that mean that the size of the actual letter "e" on the slide has also changed to be larger? 4. Place the specimen (letter "e") in the center of the field of view and switch to the power (10x) objective lens by rotating the nosepiece to bring the lens into position Be sure that the 10x objective lens locks into place. (You should hear and feel ach Adjust the focus, if necessary, and note any changes in resolution (detail) and lign intensity compared to the previous low power view. tch to the middle High 216

Answer 1

Questions 1 (The table)

Magnification of ocular lens is 10x.

So table will go like this :-

For low it's 4x (objective lens) multiplied by 10 (ocular lens) = 40x total Magnification.

For medium it's 10x (objective lens) multiplied by 10 (ocular lens) = 100x total magnification.

For high it is 45x multiplied by 10 = 450x total magnification.

For oil immersion it is 100x multiplied by 10x = 1000x total magnification.

Question 3:-

a) The letter e will be upside down and backwards when compared to e seen with unaided eye

b) the image seem to moves in opposite direction. Thus if you move image to right, it will seem to move to the left and vice versa

c) Same like (b) will happen here and it will seem to move in opposite direction. So if it is moved upward it will seem to move downward and vice versa.

d) Yes, e seems to appear larger than it is seen with unaided eyes.

e) No, microscope forms a magnified image, it does not actually change the size of the e.

Question 4:-

When we change the power of objective lens the image is much clearer, sharper and detailed in comparison with the low power objective lens.

Same happens with the light. The light is much brighter and much more sharper to the eye, giving a clearer view of the slide.

Thank you.