A source emits sound with frequency 1000 Hz. A second source emitting sound simultaneously causes a 4 Hz intensity variation to appear. What are the possible frequencies of the second source?
A)
0.004 Hz and 4000 Hz
B)
250 Hz and 4000 Hz
C)
996 Hz and 4000 Hz
D)
0.004 Hz and 250 Hz
E)
996 Hz and 1004 Hz
Question 2
Van der Waals bonding is caused by
A)
the sharing of electrons between atoms.
B)
the transfer of electrons between atoms.
C)
unequal charge distribution around neutral molecules.
D)
atoms bonding to hydrogen molecules.
E)
atoms bonding to oxygen molecules.
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