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1 month ago

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The magnitude of the Poynting vector of a planar electromagnetic wave has an average value of 0.939 W/m2. The wave is incident u

pon 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

1 answer:

Yuliya22 [3.3K]1 month ago

5 0

Answer:

The total energy can be expressed as $T = 169.02 \ J$

Explanation:

The problem states that

The Poynting vector, which measures energy flux, equals $k = 0.939 \ W/m^2$

The rectangle's length is represented by $l = 1.5 \ m$

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

The duration considered is $t = 1 \ minute = 60 \ s$

Mathematically, the overall electromagnetic energy incident on the area is given by

$T = k * A * t$

where A denotes the area of the rectangle, calculated as

$A= l * w$

By plugging in the respective values

$A= 2 * 1.5$

$A= 3 \ m^2$

Again substituting values

$T = 0.939 * 3 * 60$

$T = 169.02 \ J$

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