(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] Working Resistance, Vo or VRMS

1. The problem statement, all variables and given/known data

Hey everyone, i'm new here and just wondering if you can give me a helping hand. In my Physics homework, the following question is stated:

"A heating element for an electric fire consists of a single strand if nichrome wire wound around an insulator. The heater is required to produce 1.2kW when connected to the 230V-RMS ac mains.

(i) Calculate the working resistance of the nichrome wire.

Okay, so it's not that i don't understand how to do the question, it's just that i don't know what it's asking for. Normally it would be okay, but because the 'RMS' was thrown in, it's put me off a bit.

2. Relevant equations

Equations used:

V0 = V-RMS × √2 ------Part 1

P=IV, therefore I=P/V ------Part 2

V=IR, therefore R=V/I ------Part 3

3. The attempt at a solution

Part 1 ---- V0 = 230v × √2 = 325.269v...

Part 2 ---- I = 1200w/325.269v... = 3.689A...

Part 3 ----325.269v.../3.689A..., therefore R = 88.2 ohms

Simply, what voltage do i use? Do i convert the V-RMS into V0, or leave it alone. I've tried both ways, the latter (not seen here), gives a resistance of 44.06 ohms.

All help is greatly appreciated. Thanks.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Working Resistance, Vo or VRMS

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