Assertion : Bending a wire does not effect electrical resistance.
Reason : Resistance of wire is proportional ot resistivity of material.
AIIMS 2016, Easy
Download our app for free and get started
Resistance wire $R = \rho \frac {I}{A}$, where $\rho $ is resistivity of material which does not depend on the geometry of wire. Since when wire is bent resistivity, length and area of cross-section do not change, therefore resistance of wire also remain same.
Download our app
and get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
A potentiometer is connected between $A$ and $B$ and the balance point is obtained at $203. 6\,cm$. When the end of the potentiometer connected to $B$ is shifted to $C$, then the balance point is obtained at $24.6\,cm$. If now the potentiometer be connected between $B$ and $C$, the balance point will be at ................. $cm$
A potentiometer circuit is set up as shown. The potential gradient, across the potentiometer wire, is $k$ $volt/cm$ and the ammeter, present in the circuit, reads $1.0\,\, A$ when two way key is switched off. The balance points, when the key between the terminals $(i)$ $1$ and $2$ $(ii)$ $1$ and $3,$ is plugged in, are found to be at lengths $l_1$ and $l_2$ respectively. The magnitudes, of the resistors $R$ and $X,$ in $ohms$, are then, equal, respectively, to
A resistance of $4\,\Omega $ and a wire of length $5\,m$ and resistance $5\,\Omega $ are joined in series and connected to a cell of $e.m.f.$ $10\, V$ and internal resistance $1\,\Omega $. A parallel combination of two identical cells is balanced across $300\, cm$ of the wire. The $e.m.f.$ $E$ of each cell is ........... $V$