Answer
a) $I_2=4.62W/m^2$
b) $I_2=27W/m^2$
c) $I_2=4.62W/m^2$
Work Step by Step
(a) We know that
$I_2=I_{\circ}cos^2\theta_1cos^2\theta_2$
We plug in the known values to obtain:
$I_2=(37.0W/m^2)cos^2(22.5^{\circ})cos^2(90-22.5^{\circ})$
$I_2=4.62W/m^2$
(b) As $I_2=I_{\circ}cos^2\theta_1cos^2\theta_2$
We plug in the known values to obtain:
$I_2=(37.0W/m^2)cos^2(22.5^{\circ})cos^2(0-22.5^{\circ})$
$I_2=27W/m^2$
(c) The required intensity can be determined as
$I_2=I_{\circ}cos^2\theta_1cos^2\theta_2$
We plug in the known values to obtain:
$I_2=(37.0W/m^2)cos^2(22.5^{\circ})cos^2(45+22.5^{\circ})$
$I_2=4.62W/m^2$
