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

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The discussion addresses the apparent contradiction between the two equations for power loss: P = I^2R and P = V^2/R. The first equation indicates that power loss increases with resistance when current is constant, while the second suggests that power loss decreases with increased resistance when voltage is constant. This confusion arises from the different conditions under which each equation is applied. Both equations are consistent but highlight different scenarios in electrical systems. Understanding the context of fixed current versus fixed voltage clarifies the relationship between resistance and power loss.
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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