The change of energy : 4.8744 x 10⁺¹⁹ J
Radiation energy is absorbed by photons
The energy in one photon can be formulated as
[tex]\large{\boxed{\bold{E\:=\:h\:.\:f}}}[/tex]
Where
h = Planck's constant (6,626.10⁻³⁴ Js)
f = Frequency of electromagnetic waves
f = c / λ
c = speed of light
= 3.10⁸
λ = wavelength
The wavelength is 4078 A = 4.078 x 10⁺⁷ m
[tex]\tt E=h.\dfrac{c}{\lambda}\\\\E=6.626\times 10^{-34}\times \dfrac{3.10^8}{4.078\times 10^{-7}}\\\\E=4.8744\times 10^{-19}~J[/tex]