What Is the Maximum Electric Field from a 100W Light Bulb at 1 Meter?

AI Thread Summary
To calculate the maximum electric field E at 1 meter from a 100W light bulb, the intensity I must be determined first, which is the power per unit area. The total power radiated by the bulb is distributed over the surface area of a sphere with a radius of 1 meter, leading to the intensity being 100W divided by the surface area of the sphere. The relationship between intensity and electric field is given by the equation I = (1/2)(8.85x10^-12)(c)E^2, where c is the speed of light. The confusion arises from not having a specified unit area, but the calculation can proceed using the sphere's surface area. Ultimately, the maximum electric field can be derived from the intensity calculated from the bulb's power.
sgoeke
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Homework Statement


What is the maximum value of the electric field E at 1.0 m from a 100 W light bulb radiating in all directions?


Homework Equations


I feel like I should use this equation: I=(1/2)(8.85x10^-12)(c)E^2


The Attempt at a Solution


When I used that equation, I didn't get the right answer. But I guess I'm confused since intensity is W/m^2 and we're not given the unit area.
 
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sgoeke said:

Homework Statement


What is the maximum value of the electric field E at 1.0 m from a 100 W light bulb radiating in all directions?


Homework Equations


I feel like I should use this equation: I=(1/2)(8.85x10^-12)(c)E^2


The Attempt at a Solution


When I used that equation, I didn't get the right answer. But I guess I'm confused since intensity is W/m^2 and we're not given the unit area.

You have 100W of light going through the surface area of a sphere that has a radius of 1 meter...
 
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