Need your help with parallel circuits

AI Thread Summary
To calculate the total resistance of a heating element with three strips in parallel, use the formula R = V²/P, where V is 12V and P is 40W. The total resistance is found to be 3.6 ohms. It's important to note that while the voltage remains constant across each strip, the power consumed is inversely proportional to the total circuit resistance. Drawing the circuit can aid in visualizing the problem. Understanding these principles is key to solving parallel circuit issues effectively.
goan
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I need to work out the total resistance of a heating element made up of 3 strips of resistive material in paralell. We are told that the unit is 12V and theheat is generated at a rate of 40W, I need to calculate the total resistance of the element. I kno I have to use the formula R=v²/r where R is the resistance, V is the voltage and r is the power(watts). i know that the voltage will be the same across all the strips but will the power, could you help me please?
 
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The power consumed is porportional to the total circiut resistance.

Thiis is a pretty straight forward problem, don't over think it.
 
Start by drawing off the circuit, that'll help.
 
goan said:
I need to work out the total resistance of a heating element made up of 3 strips of resistive material in paralell. We are told that the unit is 12V and theheat is generated at a rate of 40W, I need to calculate the total resistance of the element. I kno I have to use the formula R=v²/r where R is the resistance, V is the voltage and r is the power(watts). i know that the voltage will be the same across all the strips but will the power, could you help me please?



R(total)=3.6(ohm):blushing:
what is the problem here?
 
The power consumed is porportional to the total circiut resistance.

Inversely propotional.
 
thanks for your help guys
 
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