In an electromagnetic wave, the maximum value of the electric field is 100 Vm- 1 . The average intensity is [ ϵ 0=8.8× 10- 12C- 2N- 1m2 ]

Question

In an electromagnetic wave, the maximum value of the electric field is 100 Vm- 1 . The average intensity is [ ϵ 0=8.8× 10- 12C- 2N- 1m2 ] (A) 13.2Wm- 2 (B) 36.5 W m- 2 (C) 46.7 W m- 2 (D) 765 W m- 2

Tardigrade Admin · Accepted Answer

Iavg=(1/2)c(ϵ )0(E0)2 ⇒ Iavg=(1/2)× 3× (10)8× 8.8× (10)- 12× (100)2 ⇒ Iavg=13.2Wm- 2

Q. In an electromagnetic wave, the maximum value of the electric field is $100 V m^{- 1}$ . The average intensity is [ $ϵ_{0} = 8.8 \times 1 0^{- 12} C^{- 2} N^{- 1} m^{2}$ ]

$13.2 W m^{- 2}$

$36.5 W m^{- 2}$

$46.7 W m^{- 2}$

$765 W m^{- 2}$

$I_{a vg} = \frac{1}{2} c (ϵ)_{0} (E_{0})^{2}$
$\Rightarrow I_{a vg} = \frac{1}{2} \times 3 \times (10)^{8} \times 8.8 \times (10)^{- 12} \times (100)^{2}$
$\Rightarrow I_{a vg} = 13.2 W m^{- 2}$

Q. In an electromagnetic wave, the maximum value of the electric field is 100Vm−1 . The average intensity is [ ϵ0​=8.8×10−12C−2N−1m2 ]

13.2Wm−2

36.5Wm−2

46.7Wm−2

765Wm−2