What is Ohm’s law? Explain how it is used to define the unit of resistance.
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Ohm’s law gives a relationship between current (I) and potential difference (V). According to ohm’s law: At constant temperature, the current flowing through a conductor is directly proportional to the potential difference across its ends. If I is the current flowing through a conductor and V is the p.d. across its ends, then according
to the ohm’s law:
$\text{I}\propto\text{V}$
or, $\text{I}\propto\text{V}$
or, V = RI
or, $\text{R}=\frac{\text{V}}{\text{I}}$
where, R is a constant called ''resistance'' of the conductor.
The unit of resistance is ohm.
If V = 1 volt and I = 1 amp, then $\text{R}=\frac{1}{1}=1\text{ohm}$
Thus, 1 ohm is the resistance of a conductor such that when a potential difference of 1 volt is applied to its ends, a current of 1 amp flows through it.
to the ohm’s law:
$\text{I}\propto\text{V}$
or, $\text{I}\propto\text{V}$
or, V = RI
or, $\text{R}=\frac{\text{V}}{\text{I}}$
where, R is a constant called ''resistance'' of the conductor.
The unit of resistance is ohm.
If V = 1 volt and I = 1 amp, then $\text{R}=\frac{1}{1}=1\text{ohm}$
Thus, 1 ohm is the resistance of a conductor such that when a potential difference of 1 volt is applied to its ends, a current of 1 amp flows through it.
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