What, Approximately, Are the Dimensions of the Smallest Object on Earth

question 39

Multiple Choice

What, approximately, are the dimensions of the smallest object on Earth that the astronauts can resolve by eye at 200 km height from the space shuttle? Assume λ = 500 nm light and a pupil diameter D = 0.50 cm. Assume eye fluid has an average n = 1.33.

• A) 150 m
• B) 100 m
• C) 250 m
• D) 25 m
• E) 18 m

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Definitions:

Carbon Dioxide

A colorless, odorless gas produced by burning carbon and organic compounds and by respiration. It is naturally present in air and is absorbed by plants in photosynthesis.

Terrestrial Plants

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Aquifer

Rock layers that contain water and release it in appreciable quantities to wells or springs.

Rate Of Recharge

The speed at which an aquifer or a rechargeable battery regains its capacity or is refilled after use.