What is the value of the square root of the mean of the square current?

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Homework Help Overview

The problem involves calculating the average of the square of an rms current drawn by a television set from a power line. The context is within electrical engineering, specifically focusing on the concept of root mean square (rms) values.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the distinction between finding the square of the average versus the average of the square. There are attempts to clarify the meaning of rms and how it relates to the problem at hand.

Discussion Status

The discussion is ongoing, with participants providing hints and clarifications regarding the interpretation of the problem. Some guidance has been offered about the relationship between rms values and the average of the square, but no consensus has been reached on the correct approach.

Contextual Notes

Participants are navigating the definitions and calculations related to rms values, with some confusion about the terms used in the problem statement. There is an indication of differing interpretations regarding the calculations involved.

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Homework Statement



A television set draws an rms current of 2.25 A from a 60 Hz power line.
What is the average of the square of the current?


Homework Equations



Irms=square root of average of isquared

The Attempt at a Solution



i found the average of the current to be 0. I just keep getting 2.53, which is the wrong answer!
 
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You're not being asked to find the square of the average which is zero, you're supposed to find the average of the square.
 
Hint: What's another word for average?
 
do you do 2.25squared?
 
Think about rms (root mean squared) and how the rms value is calculated. Compare that to the question.
 
rms=1/squarerootof2*amplitude? i get 2.24
 
Root Mean Square means we're taking the square root of the mean of the square. For a standard sine wave with maxima and minima at +1 and -1 and a mean of 0, when it is squared the maxima and minima become +1 and 0 and the mean is 0.5. The square root of the mean is 0.707.

You are given the square root of the mean (average) of the square. If you square that value, what do you have?
 

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