Compound Microscope: the Objective and the Eyepiece of a Microscope

question 43

Multiple Choice

Compound microscope: The objective and the eyepiece of a microscope have focal lengths of 4.00 mm and 25.0 mm, respectively. The objective produces a real image 30 times the size of the object. The final image is viewed at infinity, and the near point of the microscope user is at 25.0 cm. What is the distance between the object and the focal point of the objective?

• A) 0.13 mm
• B) 0.18 mm
• C) 0.23 mm
• D) 0.28 mm
• E) 0.33 mm

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Definitions:

Citric Acid Cycle

A key metabolic pathway that breaks down carbohydrates, fats, and proteins into carbon dioxide and water while generating energy-rich molecules like ATP.

NADH

Nicotinamide adenine dinucleotide (reduced form) is a coenzyme found in all living cells, involved in redox reactions, carrying electrons from one reaction to another.

Ketone Bodies

Compounds, including acetone, acetoacetic acid, and beta-hydroxybutyric acid, that are produced as by-products when fatty acids are broken down for energy in the liver and kidney.

Urine

A liquid by-product of metabolism in humans and many animals, excreted by the kidneys and stored in the bladder until elimination.