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The intensity of sunlight under the clear sky is 836 W/m2. The speed of light is 2.99792 × 108 m/s. How much electromagnetic energy is contained per cubic meter near the Earth’s surface?

Answer 1

Here I am going to try but take it as a suggestion only...

According to your question you need a kind of energy density in #"Joules"/m^3#. Observing the units of your data you have: Power divided by area or #"Watts"/m^2="Joule"/(s*m^2)# By dividing it by velocity (in #m/s#) you get: #("Joule"/(s*m^2))/(m/s)="Joules"/m^3# So it should be: #836/(2.99792xx10^8)=2.7886xx10^-6J/m^3#

Kindly inform me of this! :-)

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Answer 2

Luke Allen

To calculate the electromagnetic energy per cubic meter near the Earth's surface, you can use the formula:

Energy density = Intensity of sunlight / Speed of light

Substituting the given values:

Energy density = 836 W/m^2 / 2.99792 × 10^8 m/s

Energy density ≈ 2.79 × 10^-6 J/m^3

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.