A 27 mW laser beam has a cross-sectional area of 10 mm2. The magnitude of the maximum electric field in this electromagnetic wave is given by :
[ Given permittivity of space = 9 x 10-12 SI units, Speed of light c = 3 x 108 m/s ]
2 kV/m
1.4 kV/m
1 kV/m
0.7 kV/m
Intensity of EM wave -
- wherein
= Permittivity of free space
= Electric field amplitude
c = Speed of light in vacuum
&
(1) = (2)
2 kV/m
Option 2)1.4 kV/m
Option 3)1 kV/m
Option 4)0.7 kV/m
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