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

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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..