What is the magnitude of the Electric field inside a light wave?

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The magnitude of the electric field inside a light wave varies significantly, with values ranging from about 10^-6 N/C for weak light sources to over 10^6 N/C for intense beams like lasers. The intensity of light is directly related to the amplitude of the electric field, with a typical intensity of 1300 W/m^2 corresponding to approximately 1000 N/C. The intensity of sunlight at 1 AU may not encompass the entire electromagnetic spectrum, focusing mainly on heat and visible light. Detection capabilities can identify intensities as low as 10^-14 W/m^2, while powerful sources can reach up to 10^12 W/m^2, illustrating the vast range of electric field magnitudes. Understanding these variations is crucial for grasping the nature of light and its interactions.
silverdiesel
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I know the magnitude varys a lot, but I am just looking for some basic intuitive idea of light. Is the magnitude of light from my computer screen on the order of 10^6 N/C or more like 10^-6 N/C?
 
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Nevermind, I finally found it in my gen phys 2 book derived from the Intensity. 1300 W/m^2 ~ 1000 N/C
 
I think the figure you quoted is the value for the intensity of light from the sun at a distance of 1 AU. But I'm not sure if that includes the entire EM spectrum, or just heat and visible light.
 
Classically at least, the field can vary widely, a laser beam for example might have a huge E field (enough to induce air to ionise in some cases). The light from a star obviously has a much weaker E field. Note that the amplitude of the E field is related to the intensity of a light beam. To give you an idea in terms of numbers (in intensity), we can detect 10^-14 W/m^2 and produce 10^12 W/m^2 (as a conservative estimate), that's 26 orders of magnitude right there.

Claude.
 
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