Instantaneous Energy Density: 501 N/C

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The instantaneous energy density in an electromagnetic field with an electric field value of 501 N/C is calculated using the formula: Instantaneous Energy Density = (Electric Field)^2 / (2 * Permittivity of Free Space). Substituting the values, the calculation yields an energy density of approximately 125.50 mJ/m^3. This result is derived from the electric field strength and the permittivity of free space. Thus, the instantaneous energy density at that point is 125.50 mJ/m^3.
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At a given instant of time in an electromagnetic field the Electric Field has a value of 501 N/C. To the nearest hundredth of a mJ/m3, what is the instantaneous energy density at that point?
 
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The instantaneous energy density at that point can be calculated by using the formula:

Instantaneous Energy Density = (Electric Field)^2 / (2 * Permittivity of Free Space)

Substituting the given value of electric field (501 N/C) and the value of permittivity of free space (8.85 * 10^-12 F/m), we get:

Instantaneous Energy Density = (501 N/C)^2 / (2 * 8.85 * 10^-12 F/m)

= 125,501 N^2 / C^2 * m / F

= 125,501 * 10^6 mJ/m^3

= 125.50 mJ/m^3

Therefore, the instantaneous energy density at that point is approximately 125.50 mJ/m^3.
 
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