Answer
$E = 7.6\times 10^{5}~J$
Work Step by Step
We can find the power received by the person's back as:
$P = I~A$
$P = (1400~W/m^2)(0.30~m)(0.50~m)$
$P = 210~W$
We can find the energy that falls on the person's back in 1.0 hour as:
$E = P~t$
$E = (210~W)(3600~s)$
$E = 7.6\times 10^{5}~J$
