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A red LED emits light of 0.1 watt unifor...

A red LED emits light of 0.1 watt uniformaly around it. The amplitude of the electric field of the light at a distance of 1m from the diode is

A

1.73 V/m

B

2.45 V/m

C

5.48 V/m

D

7.75 V/m

Text Solution

Verified by Experts

The correct Answer is:
B
Intensity `I=1/2epsilon_0E_0^2C`
`E_0` is amplitude of the electric field of the light
`p/(4pir^2)=1/2epsilon_0E_0^2Cimplies E_0=sqrt((2p)/(4pir^2Cepsilon_0))=2.45 V//m`
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