A magnifying glass produces an angular magnification of 7. What is the focal length of this lens if a person whose near point is 28 cm reads a book using this magnifying glass?
A)
2 cm
B)
3 cm
C)
4 cm
D)
5 cm
E)
6 cm
C
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Nuclear Reactions: The equation shows a fission reaction:
U + 
n ? 
Nb + X + 4 
nWhat is the missing term X in the equation?
A. 
Ag
B. 
Sb
C. 
Sb
D. 
Ag
E. 
Sb
An effective theory must
A) have been proven. B) must have been around for centuries or longer. C) be continuously tested. D) include mathematical formulae.
Bond energies increase in going from C-N (lowest) to C-O to C-F (highest). Explain this trend based upon the atomic sizes of these atoms as deduced from their positions in the periodic table
A) In going from nitrogen to oxygen to fluorine the atoms get larger. This means a greater nuclear charge, which translates into stronger chemical bonds. B) In going from nitrogen to oxygen to fluorine the atoms get smaller. This means a greater nuclear charge, which translates into stronger chemical bonds. C) In going from nitrogen to oxygen to fluorine the atoms get larger. This means that the bonding atoms are farther apart, which translates into a greater bond energy. D) In going from nitrogen to oxygen to fluorine the atoms get smaller. This means that the bonding atoms are closer together, which translates into a greater bond energy.
An automobile engine operates with an overall efficiency of 12%. How much energy is delivered as waste heat (in gallons of gasoline) for each 10 gallons of fuel burned?
a. 1.2 b. 8.8 c. 6.5 d. 4.7 e. 7.5