Question
Explain Ohm's law.
✓
Answer
→Statement of Ohm's law :
"Under a definite physical condition, the current (I) flowing through the conductor is directly proportional to the potential difference (V) applied across its ends."
→This law was discovered by G.S. Ohm.
→Imagine a conductor in which a current I is flowing and the potential difference between the ends of the conductor is V .
→According to Ohm's law
$\begin{aligned}
V & \propto I \\
\therefore \quad V & = RI
\end{aligned}$
Where R is the constant of proportionality. It is called the resistance of the conductor.
→The SI unit of resistance is ohm and it is denoted by $\Omega$.
→The resistance depends on the
(i) material
(ii) temperature and
(iii) dimensions of the conductor.
"Under a definite physical condition, the current (I) flowing through the conductor is directly proportional to the potential difference (V) applied across its ends."
→This law was discovered by G.S. Ohm.
→Imagine a conductor in which a current I is flowing and the potential difference between the ends of the conductor is V .
→According to Ohm's law
$\begin{aligned}
V & \propto I \\
\therefore \quad V & = RI
\end{aligned}$
Where R is the constant of proportionality. It is called the resistance of the conductor.
→The SI unit of resistance is ohm and it is denoted by $\Omega$.
→The resistance depends on the
(i) material
(ii) temperature and
(iii) dimensions of the conductor.
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