sp;emerged about 1957. Townes and Arthur Schawlow, then at Bell
Telephone Laboratories, wrote a long paper outlining the conditions needed to amplify
stimulated emission of visible light waves. At about the same time, similar ideas
crystallized in the mind of Gordon Gould, then a 37- year-old graduate student at
Columbia, who wrote them down in a series of notebooks. Townes and Schawlow
published their ideas in a scientific journal, Physical Review Letter, but Gould filed a
patent application. Three decades later, people still argue about who deserves the credit
for the concept of the laser.
1. The word "coin" in line 1 could be replaced by
(A) created
(B) mentioned
(C) understood
(D) discovered
2. The word "intervention" in line 4 can best be replaced by
(A) need
(B) device
(C) influence
(D) source
3. The word "it" in line 5 refers to
(A) light bulb
(B) energy
(C) molecule
(D) atom
4. Which of the following statements best describes a laser?
(A) A device for stimulating atoms and molecules to emit light
(B) An atom in a high-energy state
(C) A technique for destroying atoms or molecules
(D) An instrument for measuring light waves
5. Why was Towne’s early work with stimulated emission done with microwaves?
(A) He was not concerned with light amplification
(B) It was easier to work with longer wavelengths.
(C) His partner Schawlow had already begun work on the laser.
(D) The laser had already been developed
6. In his research at Columbia University, Charles Townes worked with all of the following EXCEPT
(A) stimulated emission
(B) microwaves
(C) light amplification
(D) a maser
7.In approximately what year was th
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