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

question 78

Multiple Choice

The focal lengths of the objective and the eyepiece in a microscope are 0.29 cm and 2.5 cm, respectively. An object is placed 0.3 cm from the objective. The image of this object is viewed with the eyepiece adjusted for minimum eyestrain. What is the distance between the objective and the eyepiece?

• A) 9.85 cm
• B) 10.1 cm
• C) 10.4 cm
• D) 11.2 cm
• E) 11.5 cm

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Definitions:

Inducible Operon

A cluster of genes in bacteria that is turned on (or induced) in response to the presence of a specific substrate, allowing the bacteria to adapt to environmental changes.

Repressible Operon

A regulatory mechanism in genetics where the presence of a certain substance inhibits gene transcription, typically found in prokaryotic organisms.

Lactose Operon

A cluster of genes in bacteria that encodes enzymes responsible for the metabolism of lactose, regulated by the availability of this sugar.

Tryptophan Operon

A group of genes that are regulated together, involved in the biosynthesis of the amino acid tryptophan in bacteria.