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PainterGuy
Mar15-11, 01:55 AM
hello all the people,

in the formula V=IR where V is voltage, I is current and R is resistance. suppose the value of R slowly decreases to "0". in real world, i have been said, it is impossible to have some conductor with zero resistance. which means R tends toward zero without ever reaching it. now i think this is a calculus problem with which you fine people can help me.

suppose V is constant, say, 5V. how do we take limit such that when R tends to "0", "I" become infinite. please show me the light. i'm grateful.

cheers

HallsofIvy
Mar15-11, 06:09 AM
All you can say, or need to say, is that the limit of I as R goes to 0 does not exist.

PainterGuy
Mar15-11, 07:14 AM
hello HallsofIvy,

could you please lead me to the step where we come to the conclusion that limit does not exist. please show me the steps. much obliged.

let V=5, let

5=IR
I=5/R
???

edit:--- what it means in this real world problem to say limit does not exist? is this not possible to say that as R goes to 0, I goes toward infinity? please show me the light.