Electromagnetic WavesEasy
Question
A red LED emits light at 0.1 watt uniformly around it. The amplitude of the electric field of the light at a distance of 1 m from the diode is:-
Options
A.5.84 V/m
B.7.75 V/m
C.1.73 V/m
D.2.45 V/m
Solution
Iav = 
ε0 E2C = 
E =
On putting value we get
= 2.45 v/m.
ε0 E2C = E =
On putting value we get
= 2.45 v/m.
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