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Question
The bellows of an adjustable camera can be extended so that the largest film to lens distance is one and one-half times the focal length. If the focal length is 12 cm, the nearest object which can be sharply focused on the film must be what distance from the lens?A) 12 cm
B) 24 cm
C) 36 cm
D) 48 cm
E) 72 cm
Answer
This answer is hidden. It contains 1 characters.
Related questions
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The intensity of the microwave background radiation, a remnant of the big bang:
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B) is least in directions toward the center of the galaxy
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D) is proportional to the square of the distance from us
E) is nearly the same in all directions
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Any meson is a combination of:
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Q:
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Q:
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Q:
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A) Energy
B) Baryon number
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Q:
An electron participates in:
A) the electromagnetic and weak forces only
B) the strong and weak forces only
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Q:
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A) photon
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C) neutrino
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B) greater particle number densities
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Q:
For a controlled nuclear fusion reaction, one needs:
A) high number density nand high temperature T
B) high number density nand low temperatureT
C) low number density nand high temperature T
D) low number density nand low temperature T
E) high number density nand temperature T = 0 K
Q:
The first step of the proton-proton cycle is:
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Nuclear fusion in the Sun is increasing its supply of:
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B) helium
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Q:
The purpose of a moderator in a nuclear reactor is to:
A) provide neutrons for the fission process
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The energy supplied by a thermal neutron in a fission event is essentially its:
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Q:
A certain nucleus, after absorbing a neutron, emits a and then splits into two alpha particles. The (A, Z) of the original nucleus must have been:A) 6, 2B) 6, 3C) 7, 2D) 7, 3E) 8, 4
Q:
Radioactive polonium, 214Po (Z= 84), decays by alpha emission to:
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B) 210Pb (Z= 82)
C) 214At (Z= 85)
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Q:
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Q:
Bombardment of 28Si (Z= 14) with alpha particles may produce:
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B) hydrogen and 32S (Z= 16)
C) a deuteron and 27Al (Z= 13)
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