Electromagnetic coil and capacitors vs resistance

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SUMMARY

The discussion centers on the formulas for energy storage in electromagnetic coils and capacitors, specifically U=0.5LI² for coils and U=0.5CV² for capacitors. The participants highlight that while these formulas share a structural similarity, the formula for resistance, U=RI², represents power rather than energy, as resistance does not store energy. The conversation concludes that the apparent similarities in the equations are coincidental and not indicative of a unified underlying principle.

PREREQUISITES
  • Understanding of electromagnetic coils and their inductance (L)
  • Familiarity with capacitors and their capacitance (C)
  • Knowledge of electrical resistance and power calculations
  • Basic principles of energy storage in electrical components
NEXT STEPS
  • Research the relationship between inductance and energy storage in electromagnetic coils
  • Explore the principles of capacitance and energy storage in capacitors
  • Study the differences between power and energy in electrical circuits
  • Investigate the integral of power over time for calculating energy loss in resistive components
USEFUL FOR

Electrical engineers, physics students, and anyone interested in understanding the principles of energy storage in electromagnetic systems and the differences between resistance and energy storage mechanisms.

Mohammad Hunter
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I'm not really sure if this is even scientific but while calculating how much energy is stored in electromagnetic coils and capacitors, pretty much the same formula is used:
For electromagnetic coils it's U=0.5LI2
For capacitors it's U=0.5CV2
Why I think they're the same is that in a sense L to coils is sort of the same as C to capacitors. Same goes for V and I
The formula used for resistance is pretty much the same( well resistance doesn't store energy, uses it) with a slight difference which is there's no 0.5
U=RI2
Why don't we have the same pattern for resistance? Are these formulas even realevant?
 
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Why would you expect them to be the same? As you said, R does not store energy. and ##RI^2## is not energy it is power. See my signature below.
 
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anorlunda said:
Why would you expect them to be the same? As you said, R does not store energy. and ##RI^2## is not energy it is power. See my signature below.
So energy for resistance is actually U= RIq?
But what about coils and capacitors? Are those actually the same formula adjusted for coils and capacitors? If so, what is the mother formula. Cause the conserved energy in movement shows the same pattern of K=0.5mV2 which you could say that mass to an object is sort of like L to coils and C to capacitors
Too many questions, sorry :)
 
Mohammad Hunter said:
So energy for resistance is actually U= RIq?
a

No, the energy lost in a resistance is ##\int RI^2\, dt## Or, if the power P is constant for a time T, then energy is P times T.

For the others, just consider the similarities in form of the equations to be coincidences.
 
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anorlunda said:
a

No, the energy lost in a resistance is ##\int RI^2\, dt## Or, if the power P is constant for a time T, then energy is P times T.

For the others, just consider the similarities in form of the equations to be coincidences.

Ohhhh Thank you
 
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