Power Loss Confusion: I^2R vs V^2/R

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SUMMARY

The discussion clarifies the relationship between power loss in electrical circuits using the equations P = I²R and P = V²/R. The first equation indicates that power loss increases with resistance when current is constant, while the second equation shows that power loss decreases with resistance when voltage is constant. Both equations are consistent but apply under different conditions, emphasizing the importance of understanding the context in which each equation is used.

PREREQUISITES
  • Understanding of Ohm's Law
  • Familiarity with electrical power equations
  • Knowledge of circuit analysis concepts
  • Basic grasp of fixed current and voltage scenarios
NEXT STEPS
  • Study the implications of Ohm's Law on power loss
  • Explore circuit analysis techniques for fixed current and voltage
  • Learn about the impact of resistance on power dissipation in circuits
  • Investigate real-world applications of power loss equations in electrical engineering
USEFUL FOR

Electrical engineers, physics students, and anyone interested in understanding power loss in electrical circuits will benefit from this discussion.

K Dhiraj Bhak
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Power loss doubt: power loss = I^2 R Power loss = V^2 / R But the 2 equations are contradictory ,,, from the first equation , we can say " MORE THE RESISTANCE MORE THE POWER LOSS" from the second equation ,,, it is the other way round... Why does this happen? ( usually the 1st equation is used for power loss expression ,, but i don't know why ,, and i want to know why the second equation can't be used)
 
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K Dhiraj Bhak said:
Power loss doubt: power loss = I^2 R Power loss = V^2 / R But the 2 equations are contradictory ,,, from the first equation , we can say " MORE THE RESISTANCE MORE THE POWER LOSS" from the second equation ,,, it is the other way round... Why does this happen? ( usually the 1st equation is used for power loss expression ,, but i don't know why ,, and i want to know why the second equation can't be used)
The expressions are consistent. The first one says that the more resistance the more the power loss if the current is held fixed. Just the opposite if the voltage is held fixed.
 
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