M3: Module 3 Exam - Requires Respondus LockDown Browser + Webcam Question 1 pts
A nanometer is defined as:
A. 10-3
B. 10-6
C. 10-9
D. 10-12
Correct! C. B. D. A. Question 2
Not yet graded / 10 pts
Resolution and contrast are two critical factors that influence your ability to see an object. Explain each.
Your Answer:
Resolution is the distance between 2 objects where they are seen as separate objects. Low resolution results in seeing multiple objects as one object. Contrast is the difference in light absorption between 2 objects. Low contrast produces a high background making multiple objects difficult to see. For example, low contrast is like trying to see dark objects at night and hight contrast is like trying to see dark objects
in the light of day. Resolution refers to the distance between two objects at which the objects still can be seen as separate. Poor or low resolution means two (or more) objects may
appear as one.
Contrast is the difference in light absorbance between two objects. Poor contrast gives a high background and makes the visualization of multiple objects difficult. For instance, trying to identify 2 dark colored objects at night (low light = low contrast) versus the same 2 objects in the middle of a sunny afternoon (bright light against 2 dark objects = high contrast). Question 3 pts
Assuming a constant (non-adjustable) light source power, identify the part of the microscope you would adjust to limit the amount of light entering the microscope.
Select all that apply.
Correct! Iris diaphragm The iris controls the amount of light that passes through the sample and into the objective lens. Thus, it can be adjusted (opened or closed) to alter the amount of light. Eye piece Condenser Objective Question 4
Not yet graded / 5 pts
What is the total magnification (relative to your eye) of a sample imaged with a 20x objective and a 15x eyepiece? Show your math.
Your Answer:
20x X 15x = 300x total magnification