The Secondary Mirror of a Telescope Whose Primary Mirror Is

question 121

Multiple Choice

The secondary mirror of a telescope whose primary mirror is 4 m in diameter has a diameter of 0.5 m. What fraction of the incoming light is obstructed by this secondary mirror?

• A) about 1.6%
• B) about 1/8, or 12.5%
• C) about 35%
• D) about 16%

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Definitions:

Integumentary System

The body’s covering, including the skin and its nails, glands, hair, and other associated structures.

Exocrine Glands

Glands that release their secretions through ducts onto an epithelial surface, such as sweat, salivary, and digestive glands.

Protects the Body

A generalized term for biological systems or behaviors that defend the organism against disease, infection, or injury.

Serous Membrane

An epithelial membrane that lines a body cavity that does not open to the outside of the body.