Ohm's Law - Identifying Constant in R=V/I Equation

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Ohm's Law states that the current is proportional to the potential difference, provided temperature remains constant. In the equation R = V/I, there is no fixed constant; rather, any one of the variables can be treated as constant to solve for the others. If voltage (V) is held steady, the resistance (R) can be determined by measuring the current (I). Resistance can vary with temperature, but this does not invalidate Ohm's Law; it simply means that current will change inversely with resistance fluctuations. The constant of proportionality in Ohm's Law is the resistance (R).
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according to ohm's law, the current is proportional to the potential difference provided that the temperature remains constant. so , the for equation , R= V/I, may i know which is the constant in the equation? i know the general form of direct proportion is y=kx or y/x=k but in R=V/I, i am unable to identify which is the constant. please help me with this. thank you
 
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hi there

There is no constant in there other than whichever one you want to remain constant

so for your example R = V/I ... if V is steady and you measure the current flowing in the circuit, you can establish the resistance present
so for any variation of those 3, from any 2 knowns, you can work out the unknown value

Dave
 
Lim Y K said:
according to ohm's law, the current is proportional to the potential difference provided that the temperature remains constant. so , the for equation , R= V/I, may i know which is the constant in the equation? i know the general form of direct proportion is y=kx or y/x=k but in R=V/I, i am unable to identify which is the constant. please help me with this. thank you
Why would the temperature need to remain constant? Resistance will vary with temperature but that doesn't invalidate Ohm's Law, it just means that for a fixed voltage, the current will fluctuate inversely with the resistance fluctuation
 
Ohm's law states that for constant physical conditions , the potential difference applied across a circuit is directly proportional to the current induced .

Or , V ∝i , and V=iR .

Thus the constant of proportionality , by ohm's law , is R .

I hope this helps .
 
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Qwertywerty said:
Ohm's law states that for constant physical conditions , the potential difference applied across a circuit is directly proportional to the current induced .
OR, the current induced is directly proportional to the voltage applied.
 
Qwertywerty said:
Ohm's law states that for constant physical conditions , the potential difference applied across a circuit is directly proportional to the current induced .

Or , V ∝i , and V=iR .

Thus the constant of proportionality , by ohm's law , is R .

I hope this helps .

it does make sense to me...my notes states so as well but i just needed clarification
 
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