Two wires of the same dimensions but resistivities ${\rho _1}$ and ${\rho _2}$ are connected in series. The equivalent resistivity of the combination is
Easy
Download our app for free and get startedPlay store
(b) ${R_{eq}} = {R_1} + {R_2}$==>$\frac{{{\rho _{eff.2l}}}}{A} = \frac{{{\rho _1}l}}{A} + \frac{{{\rho _2}l}}{A}$$ \Rightarrow \,{\rho _{eff.}} = \frac{{{\rho _1} + {\rho _2}}}{2}$.
art

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.*

Similar Questions

  • 1
    A current of $10\, amp$ is passing through a metallic wire of cross sectional area $4 \times 10^{-6}\, m ^{2}$. If the density of the aluminum conductor is $2.7\, gm / cc$ considering aluminum gives $1$ electrons per atom for conduction find the drift speed of the electrons is  ......... $\times 10^{-4} \,m / s$ if molecular weight of aluminum is $27 \,gm$.
    View Solution
  • 2
    A potential difference of $V$ is applied at the ends of a copper wire of length $l$ and diameter $d$. On doubling only $d$, drift velocity
    View Solution
  • 3
    To verify Ohm's law, a student connects the voltmeter across the battery as, shown in the figure. The measured voltage is plotted as a function of the current, and the following graph is obtained If $V_0$ is almost zero, identify the correct statement
    View Solution
  • 4
    In the given figure, when key $A$ is opened, the reading of the ammeter $A$ will be ........... $A$
    View Solution
  • 5
    The current density is a solid cylindrical wire of radius $R ,$ as a function of radial distance $r$ is given by $J ( r )= J _{0}\left(1-\frac{ r }{ R }\right) .$ The total current in the radial region $r =0$ to $r =\frac{ R }{4}$ will be
    View Solution
  • 6
    In the adjoining circuit, the $e.m.f.$ of the cell is $2\, volt$ and the internal resistance is negligible. The resistance of the voltmeter is $80 \,ohm$. The reading of the voltmeter will be ............. $volt$
    View Solution
  • 7
    If a copper wire is stretched to increase its length by $20 \% $. The percentage increase in resistance of the wire is $..........\%$
    View Solution
  • 8
    A battery of $6\,V$ is connected to the circuit as shown below. The current I drawn from the battery is:
    View Solution
  • 9
    $n$ identical cells each of $e.m.f.$ $E$ and internal resistance $r$ are connected in series. An external resistance $R$ is connected in series to this combination. The current through $R$ is
    View Solution
  • 10
    The equivalent resistance of the circuit shown in the figure is ............. $\Omega$
    View Solution