Intensity: 4∏D2 vs. ∏r2 Explained

Thread starter davev
Start date Dec 1, 2013
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Intensity

AI Thread Summary

The discussion clarifies the use of the formula 4∏D2 for intensity, emphasizing that it accounts for the surface area of a sphere, while ∏r2 only represents the area of a circle. Participants acknowledge the misunderstanding and express appreciation for the explanation. The distinction between the two formulas is crucial for understanding how intensity disperses in three-dimensional space. This highlights the importance of using the correct formula based on the geometric context. Understanding these differences is essential for accurate calculations in physics and related fields.

Dec 1, 2013

davev

Can someone please explain why the are used is 4∏D²? Shouldn't it just be ∏r²?

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Dec 1, 2013

sandy.bridge

The intensity spreads out over the surface of a sphere. Your formula is for the area of a circle.

Dec 1, 2013

davev

sandy.bridge said:

The intensity spreads out over the surface of a sphere. Your formula is for the area of a circle.

That makes much more sense! Can't believe I totally missed that. Thank you!

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