Electric power = I2*R= (0)2*infinity = can be any thing for open circuit?

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Discussion Overview

The discussion revolves around the concept of electric power in the context of an open circuit, specifically examining the implications of infinite resistance and zero current on power calculations. Participants explore theoretical aspects and implications of power dissipation in such scenarios.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • One participant states that in an open circuit, resistance is infinite and current is zero, leading to a power calculation of zero watts.
  • Another participant questions whether an open circuit would dissipate power in the form of heat, as a resistor does.
  • A different participant suggests examining the behavior of power as resistance approaches infinity and current approaches zero, proposing a calculation to explore the relationship.
  • One participant argues that since the current is exactly zero in an open circuit, the power must be exactly zero, contrasting this with a scenario where current approaches zero.

Areas of Agreement / Disagreement

Participants express differing views on whether power in an open circuit can be considered anything other than zero, with some asserting it must be zero while others explore the implications of the theoretical limits of resistance and current.

Contextual Notes

The discussion includes assumptions about the behavior of current and resistance in ideal conditions, and the implications of these assumptions on power calculations remain unresolved.

Who May Find This Useful

Individuals interested in electrical engineering, physics, and theoretical discussions on circuit behavior may find this discussion relevant.

leojun
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In an open circuit resistance is infinity and therefore current is zero.(voltage 220V)
power=iv=0*220=0 watt
power=I2*R=(0)2*infinity=can be any thing (V=IR)
so,is power consumed zero or any thing?
 
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A resistor dissipates power in the form of heat (eg it gets warm or even hot). Would an open circuit get hot?
 
power=I2*R

Consider what happens as R approaches infinity and I approaches zero. Let's say you start with some value of R and then keep doubling it. At each step the current halves but the power changes by how much ? Work it out.
 
Here the current does not tend to zero but is exactly 0. Hence, 0*R where R tends to infinity is exactly zero, not just any value. So power dissipated must be zero. if i would have tend to zero, i.e, went very near zero then i*Rwould have taken any value..
 

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