An excited atom can lose energy by emitting a __________.
Fill in the blank(s) with correct word
[Ques. 2] A quantum of electromagnetic radiation is a __________.
Fill in the blank(s) with correct word
[Ques. 3] The __________ occurs when electrons are emitted when light strikes the surface of a metal.
Fill in the blank(s) with correct word
[Ques. 4] Electrons in atoms
a. orbit the nucleus in well defined circular orbits
b. radiate electromagnetic energy continuously
c. act as if spread out in a cloud around the nucleus
d. behave as predicted by quantum mechanics
[Ques. 5] The mathematical model of quantum mechanics was principally founded by
a. Max Planck
b. Albert Einstein
c. Neils Bohr
d. Erwin Schroedinger
e. Werner Heisenberg.
[Ques. 6] As the temperature of a blackbody increases, the peak of its radiation curve moves
a. upward toward higher intensity
b. downward toward lower intensity
c. toward larger wavelength
d. toward smaller wavelength
e. none of the above
[Ques. 7] Which of the following devices use lasers?
a. DVD players
b. fiber optics communication systems
c. photocopiers
d. UPC price scanners
[Ques. 8] In which of the following energy level transitions for a hydrogen atom is a photon emitted?
a. n =1 to n = 2
b. n =3 to n = 2
c. n =2 to n = 1
d. n =1 to n = 4
e. n =4 to n = 3
[Ques. 9] The aurora borealis (northern lights) are caused by
a. sunlight reflecting from polar ice
b. emissions from atoms and molecules in the upper atmosphere excited by electrons from the sun
c. thunderstorms
d. an unknown process
[Ques. 10] Lasers are used
a. to produce holograms
b. in surgery
c. to measure distances between objects accurately
d. in DVD and compact disc players
e. all of the above
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