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A lamp emits monochromatic green light u...

A lamp emits monochromatic green light uniformly in all directions. The lamp is `3%` efficient in converting electrical power to electromagnetic waves and consumes `100 W` of power. The amplitude of the electric field associated with the electromagnetic. radiation at a distance of `10 m` from the lamp will be

A

`1.34V//m`

B

`2.68 V//m`

C

`5.36 V//m`

D

`9.37 V//m`

Text Solution

Verified by Experts

The correct Answer is:
A
`S_(av)=(P)/(4piR^(2))=(1)/(2)epsilon_(0)cE_(0)^(2) :. E_(0)=sqrt((P)/(2piR^(2)epsilon_(0)c))`
`sqrt((3)/(2xx3.14xx100xx8.85xx10^(-12)xx3xx10^(8)))=1.34V//m`
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