Which of the following represents Ohm's law?
$R=\frac{V}{I}$
$I=\frac{R}{V}$
$R=\frac{V}{I}\left (\right.$$\left.I=\frac{V}{R}\right)$.
$I=Q \cdot t$
What are the factors on which resistivity of a material depends ?
Write Joule's law of heating.
State Ohm’s law? How can it be verified experimentally? Does it hold good under all conditions? Comment.
In the figure given below, $A, B$. and $C$ are three ammeters. The ammeter $B$ reads $0.5\, A .$ (All the ammeters have negligible resistance.) Calculate
$(i)$ the readings in the ammeters $A$ and $C$. $(ii)$ the total resistance of the circuit.
The $SI$ unit of resistivity of the material is $......$