Refracting Telescope: A telescope has an angular magnification of 250 when used with a 20 mm eyepiece. What is the focal length of the objective lens?

A. 5.0 cm
B. 25 m
C. 5000 cm
D. 5.0 m
E. 2.5 m


Answer: D

Physics & Space Science

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Three spaceships A, B, and C are in motion as shown in the figure. The commander on ship B observes ship C approaching with a relative velocity of 0.83c

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The grooves and ridges on Ganymede are thought to

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The ripple frequency of a bridge rectifier is

a. double the input frequency. b. the same as the input frequency c. triple the input frequency. d. quadruple the input frequency.

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When counting particle-in-a-box quantum states in three dimensions, why do we divide the “volume” of only one eighth of a full spherical shell by the “volume” per quantum state? Why not the full shell’s volume?

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Physics & Space Science