Determine the rms value for the given function

AI Thread Summary
The discussion focuses on calculating the RMS value of the function v(t) = 15 + 10cos(20πt). The formula used for RMS is Vrms = √(1/T * ∫T0 v^2 dt, and the initial attempt led to an incorrect result of 24.98V. The correct approach involves recognizing the contributions of the constant and cosine terms in the integration. The accurate RMS value is determined to be 16.58V, highlighting a mistake in the integration process. Proper application of the formula yields the correct result.
Northbysouth
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Homework Statement



Determine the rms value of v(t) = 15 + 10cos(20πt)


Homework Equations



Vrms = √(1/T*∫T0v2dt

The Attempt at a Solution



√(10*∫0.10[15+10cos(20πt)]2dt

Unless, I'm much mistaken I should be able to plug the equation into the formula I have given above. I used the integral function on my calculator to do the calculation and I got 24.98V but the answer is supposed to be 16.58V

Any suggestions for where I'm going wrong?
 
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Your setup is correct. You must have made a mistake in the integration with your calculator.
 
Vrms = √15^2+(10/√2)^2 = 16.58 V
 

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