An Astronomical Telescope Has an Objective of Diameter 20 Cm

question 17

Multiple Choice

An astronomical telescope has an objective of diameter 20 cm with a focal length of 180 cm.The telescope is used with an eyepiece of focal length 30 mm.What is the angular magnification of this telescope?

• A) 360 x
• B) 60 x
• C) 540 x
• D) 6 x
• E) 180 x

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Definitions:

Nitrogen

A colorless, odorless gas that is the most abundant element in the Earth's atmosphere, essential for plant and animal life.

Argon

A noble gas element with atomic number 18, colorless and odorless, used in lighting and welding due to its inertness.

Baking Soda

A common name for sodium bicarbonate, a chemical compound used in baking as a leavening agent.

Elemental Symbol

A one or two-letter abbreviation derived from the element's name in English or Latin, representing a chemical element on the periodic table.