In order for a telescope to produce a large magnification one would select lenses of
A. short focal length for both objective and eyepiece.
B. large focal length for the objective and short focal length for the eyepiece.
C. short focal length for the objective and long focal length for the eyepiece.
D. large focal length for both objective and eyepiece.
Answer: B
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A 10-gram wire that is 6.0 m long is under tension. When a transverse wave of frequency 280 Hz travels along the wire, its wavelength is 0.60 m, and its amplitude is 8.4 mm
How much time does it take for a crest of the transverse wave to travel the length of the wire? A) 36 ms B) 31 ms C) 40 ms D) 44 ms E) 49 ms
A lab has a new material they must test in order to determine its nature. Which test will determine whether the substance is a conductor, insulator, or semiconductor?
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Which of the following statements about electrochemistry is not true?
A) It is the study of how electrical energy and chemical reactions are related. B) It involves the use of a set of oxidation-reduction reactions to produce electrical current. C) It involves the use of electrical current to produce an oxidation-reduction reaction. D) It is the study of how electrons are transferred from one chemical compound to another. E) All of the above are true.
In a star, the condition of balance between the inward force of gravity and the outward force of thermal and radiation pressure is known as ______________ equilibrium
Fill in the blank(s) with correct word