A flood light is covered with a fitter than transmits red light. The electric field of the emerging beam is represented a sinusolidal plane wave
`E_(x)=36 sin (1.20xx10^(7)z-3.6xx10^(15)t) V//m`
The average intensity of beam is `"watt"//("metre")^(2)` will be

Options

A. `6.88`
B. `3.44`
C. `1.72`
D. `0.86`

Answer

c

Explanation

Here, `E_0=36V//m,` Now Average Intensity
`I_(av)=1/2 in_0 E_0^2xxc`
`=(8.85xx10^(-12)xx(36)^2xx3xx10^8)/2`
`=1.72W//m^2`