A 7.5 × 1014 Hz laser emits a 7.7-?s pulse, 5.0 mm in diameter, with a beam energy density of 0.51 J/m3. What is the amplitude of the electric field of the emitted waves?
(c = 3.00 × 108 m/s,
?0 = 4? × 10-7 T • m/A, ?0 = 8.85 × 10-12 C2/N • m2)
A) 340 kV/m
B) 480 kV/m
C) 240 kV/m
D) 150 kV/m
E) 120 kV/m
A
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What is the magnetic energy density in a volume where the magnetic field is 4.0 mT?
a. 
b. 
c. 
d. 
e. 
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