The Focal Lengths of the Objective and the Eyepiece in a Microscope

question 100

Multiple Choice

The focal lengths of the objective and the eyepiece in a microscope are 0.29 cm and 2.50 cm, respectively. An object is placed at 0.30 cm from the objective lens and the image of this object is viewed with the eyepiece adjusted for minimum eyestrain. The near-point distance of the person using the microscope is 25.0 cm. What is the final magnification of the microscope?

• A) -190
• B) -240
• C) -300
• D) -310
• E) -470

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Definitions:

Salivation

The secretion of saliva in the mouth, which is triggered by the presence or thought of food, aiding in digestion.

Extinction

In psychology, the gradual weakening and eventual disappearance of a conditioned response when the conditioned stimulus is no longer paired with the unconditioned stimulus.

Gradual Weakening

A slow reduction in strength, intensity, or power of something, often occurring over time.

Conditioned Response

A learned reaction to a previously neutral stimulus that has been repeatedly presented along with an unconditioned stimulus.