A wire $50\, cm$ long and $1\;mm^2$ in cross -section carries a current of $4\; A$ when connected to a $2\; V$ battery. The resistivity of the wire is
AIPMT 1994, Medium
Download our app for free and get started
$R = \frac{V}{i} = \rho \frac{l}{A}$ $ \Rightarrow $ $\frac{2}{4} = \rho \frac{{50 \times {{10}^{ - 2}}}}{{{{(1 \times {{10}^{ - 3}})}^2}}}$
$ \Rightarrow \rho = 1 \times {10^{ - 6}}\,\Omega m$.
Download our appand get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
Similar Questions
- 1$A$ simple circuit contains an ideal battery and a resistance $R$. If a second resistor is placed in parallel with the first,View Solution
- 2The resistance of the series combination of two resistance is $S$. When they are joined in parallel the total resistance is $P$. If $S = nP$, then the minimum possible value of $n$ isView Solution
- 3In the given circuit diagram, find the current passing through wire $CD$ (in ampere)View Solution
- 4In the circuit shown below, The reading of the voltmeter $V$ is ...........View Solution
- 5In a wire of cross section radius $r,$ free electrons travel with drift velocity $v$ when a current $I$ flows through the wire. What is the current in another wire of half the radius and of the same material when the drift velocity is $2v$ ?View Solution
- 6View SolutionOhm's law fails in
- 7The resistances of the platinum wire of a platinum resistance thermometer at the ice point and steam point are $8 \Omega$ and $10 \Omega$ respectively. After inserting in a hot bath of temperature $400^{\circ} \mathrm{C}$, the resistance of platinum wire is:View Solution
- 8A wire of resistance $R$ and radius $r$ is stretched till its radius became $r / 2$. If new resistance of the stretched wire is $x R$, then value of $x$ is $\qquad$View Solution
- 9The equivalent resistance between $A$ and $B$ is $......$View Solution
- 10Find potential difference across $24\,\Omega $ ............. $\mathrm{volt}$View Solution
