Module 3 Exam Review
Question 1
Question:
A nanometer is defined as:
Answer choices:
A. 10⁻¹² meters
B. 10⁻⁶ meters
C. 10⁻³ meters
D. 10⁻⁹ meters
Correct answer:
D. 10⁻⁹ meters
Explanation:
A nanometer (nm) equals 10⁻⁹ meters, which is commonly used to measure viruses,
proteins, and wavelengths of visible light.
Why the other options are incorrect:
A. 10⁻¹² meters = picometer
B. 10⁻⁶ meters = micrometer
C. 10⁻³ meters = millimeter
Question 2
Question:
Resolution and contrast are two critical factors that influence your ability to see an object.
Explain each.
Correct answer summary:
Resolution:
Resolution is the minimum distance between two objects at which they can still be
seen as separate.
Contrast:
Contrast is the difference in light absorption between an object and its background.
, Explanation:
Poor resolution causes two nearby objects to appear as one. Poor contrast makes
specimens difficult to distinguish from their background.
Example:
Low contrast → dark objects in darkness
High contrast → dark objects against bright background
Question 3
Question:
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.
Answer choices:
A. Eyepiece
B. Iris diaphragm
C. Objective lens
D. Condenser
Correct answer:
B. Iris diaphragm
Explanation:
The iris diaphragm controls how much light passes through the specimen and enters the
objective lens.
Why the other options are incorrect:
Eyepiece
→ Magnifies image, does not control light amount
Objective lens
→ Controls magnification and resolution
Condenser
→ Focuses light, but does not primarily regulate intensity
Question 4
Question:
What is the total magnification of a sample imaged with a 60× objective and a 10×
eyepiece?
Question 1
Question:
A nanometer is defined as:
Answer choices:
A. 10⁻¹² meters
B. 10⁻⁶ meters
C. 10⁻³ meters
D. 10⁻⁹ meters
Correct answer:
D. 10⁻⁹ meters
Explanation:
A nanometer (nm) equals 10⁻⁹ meters, which is commonly used to measure viruses,
proteins, and wavelengths of visible light.
Why the other options are incorrect:
A. 10⁻¹² meters = picometer
B. 10⁻⁶ meters = micrometer
C. 10⁻³ meters = millimeter
Question 2
Question:
Resolution and contrast are two critical factors that influence your ability to see an object.
Explain each.
Correct answer summary:
Resolution:
Resolution is the minimum distance between two objects at which they can still be
seen as separate.
Contrast:
Contrast is the difference in light absorption between an object and its background.
, Explanation:
Poor resolution causes two nearby objects to appear as one. Poor contrast makes
specimens difficult to distinguish from their background.
Example:
Low contrast → dark objects in darkness
High contrast → dark objects against bright background
Question 3
Question:
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.
Answer choices:
A. Eyepiece
B. Iris diaphragm
C. Objective lens
D. Condenser
Correct answer:
B. Iris diaphragm
Explanation:
The iris diaphragm controls how much light passes through the specimen and enters the
objective lens.
Why the other options are incorrect:
Eyepiece
→ Magnifies image, does not control light amount
Objective lens
→ Controls magnification and resolution
Condenser
→ Focuses light, but does not primarily regulate intensity
Question 4
Question:
What is the total magnification of a sample imaged with a 60× objective and a 10×
eyepiece?
