Understanding Joule's Law and Power: How Does It Relate to Heat and Resistance?

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Joule's law defines the relationship between heat (Q), current (I), resistance (R), and time (t) as Q=I^2*R*t, indicating that heat generated is proportional to resistance when current and time are constant. When resistors are connected in series, the total resistance increases, leading to greater heat generation compared to parallel connections, where total resistance decreases. Power is described as the rate of change of energy, linking energy to heat generation. The discussion clarifies that total resistance in parallel is indeed less than in series. Understanding these principles is crucial for analyzing electrical circuits and their thermal effects.
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Hello, i want to ask 2 questions:
1-what is the difference between joule's heat and power?
2-We have 2 different resistors.How joule's heat ,which is created in them, will change if they connect to a steady voltage source:(a)in series,(b)in parallel
Thank you
 
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What are your thoughts on the subject?

Is Joule's heat just energy or something else? How does energy relate to power?


Also, how is total resistance affected when resistors are in series/parallel?
 
total resistance in series is Rt=R1+R2+...+Rn and in parallel 1/Rt=1/R1+1/R2+...+1/Rn.
Joule's law sais Q=I^2*R*t where Q the heat generated by a constant current.If (I) and (t) are constant Q is proportionate to R so in series Q will increase more than when the resistors are in parallel.Correct?
 
I&Tstudent said:
total resistance in series is Rt=R1+R2+...+Rn and in parallel 1/Rt=1/R1+1/R2+...+1/Rn.
Joule's law sais Q=I^2*R*t where Q the heat generated by a constant current.If (I) and (t) are constant Q is proportionate to R so in series Q will increase more than when the resistors are in parallel.Correct?

Wouldn't the total resistance in parallel be less than in series?
 
rock.freak667 said:
Wouldn't the total resistance in parallel be less than in series?
thats what i said
 
I&Tstudent said:
thats what i said

Sorry I read that incorrectly. But you are correct.

and remember that power is the rate of change of energy.
 
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