Question

The magnitude of the Poynting vector of a planar electromagnetic wave has an average value of 0.939 W/m2. The wave is incident upon a rectangular area, 1.5 m by 2.0 m, at right angles. How much total electromagnetic energy falls on the area during 1.0 minute

Answer 1

Answer:

The  total energy is  $T = 169.02 \ J$

Explanation:

From the question we are told that

    The  Poynting vector (energy flux ) is  $k = 0.939 \ W/m^2$

    The length of the rectangle is  $l = 1.5 \ m$

    The  width of the rectangle is  $w = 2.0 \ m$

    The time taken is $t = 1 \ minute = 60 \ s$

The total electromagnetic energy falls on the area is mathematically represented as

      $T = k * A * t$

Where A  is the area of the rectangle which is mathematically represented as

           $A= l * w$

 substituting values

         $A= 2 * 1.5$

        $A= 3 \ m^2$

substituting values

        $T = 0.939 * 3 * 60$

        $T = 169.02 \ J$