Question

Calculate the electric field associated with a LASER beam having energy density 10^6 J/cm^2

Answer 1

Energy density is given by formula

$W=\frac{εε_0E×E}{2} (1)$

Using (1) we get

$E=\sqrt{\frac{2w}{εε_0}} (2)$

In our case, w=10⁶ J/cm^2, ε=1, ε₀=8.85×10^-12

We got

E=47×10⁷ J

Answer

47×10⁷ J