The average energy-density of electromagnetic wave given by E=(50 N C- 1)sin(ω t - k x) will be nearly :-

Question

The average energy-density of electromagnetic wave given by E=(50 N C- 1)sin(ω t - k x) will be nearly :- (A) 10- 8Jm- 3 (B) 10- 7Jm- 3 (C) 10- 6Jm- 3 (D) 10- 5Jm- 3

Tardigrade Admin · Accepted Answer

Average energy density of electromagnetic wave U av =(1/2) ε0 E02=(1/2) ×(8.85 × 10-12) ×(50)2 ≈ 10-8 J m -3

Q. The average energy-density of electromagnetic wave given by $E = (50 N C^{- 1}) s in (ω t - k x)$ will be nearly :-

$1 0^{- 8} J m^{- 3}$

$1 0^{- 7} J m^{- 3}$

$1 0^{- 6} J m^{- 3}$

$1 0^{- 5} J m^{- 3}$

Average energy density of electromagnetic wave
$U_{a v} = \frac{1}{2} ε_{0} E_{0}^{2} = \frac{1}{2} \times (8.85 \times 1 0^{- 12}) \times (50)^{2}$
$\approx 1 0^{- 8} J m^{- 3}$

Q. The average energy-density of electromagnetic wave given by E=(50NC−1)sin(ωt−kx) will be nearly :-

10−8Jm−3

10−7Jm−3

10−6Jm−3

10−5Jm−3