Answer:
The energy contained is 5.856 x 10⁻⁶ J
Explanation:
Average energy density of electromagnetic radiation per unit volume is given by the equation;
[tex]U_{avg} = \frac{1}{2} \epsilon _o E_o[/tex]²
where;
[tex]\epsilon _o[/tex] is permittivity of free space
[tex]E_o[/tex] is maximum electric field strength, this can be calculated from the intensity of sun reaching the Earth's surface.
[tex]E_o = \sqrt{\frac{2I}{\epsilon_o C} }[/tex]
The intensity of sun reaching the Earth is 1350 W/m²
[tex]E_o = \sqrt{\frac{2*1350}{8.885*10^{-12}*3*10^8 } } \\\\E_o = 1008.96 \ V/m\\[/tex]
Average energy density of electromagnetic radiation per unit volume;
[tex]U_{avg} = \frac{1}{2} \epsilon_o E_o^2\\\\U_{avg} = \frac{1}{2} (8.85*10^{-12})(1008.96)^2\\\\U_{avg} = 4.505 *10^{-6} \ J/m^3[/tex]
The energy contained in a 1.30 m³ volume is given by;
E = (4.505 x 10⁻⁶)(1.3)
E = 5.856 x 10⁻⁶ J
Therefore, the energy contained is 5.856 x 10⁻⁶ J