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 ............. $volt$
Medium
Download our app for free and get started
(c) Total resistance of the circuit $ = \frac{{80}}{2} + 20 = 60\,\Omega $
$ \Rightarrow $ Main current $i = \frac{2}{{60}} = \frac{1}{{30}}A$
Combination of voltmeter and $80$ $\Omega$ resistance is connected in series with $20$ $\Omega$, so current through $20$ $\Omega$ and this combination will be same $ = \frac{1}{{30}}A$.
Since the resistance of voltmeter is also $80$ $\Omega$, so this current is equally distributed in $80$ $\Omega$ resistance and voltmeter (i.e.$\frac{1}{{60}}A$ through each)
$P.D.$ across $80$ $\Omega$ resistance $ = \frac{1}{{60}} \times 80 = 1.33\,V$
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.*
In the given potentiometer circuit length of the wire $AB$ is $3\,m$ and resistance is $R = 4.5 \,\Omega.$ The length $AC$ for no deflection in galvanometer is ................ $\mathrm{m}$
What equal length of an iron wire and a copper-nickel alloy wire, each of $2 \; {mm}$ diameter connected parallel to give an equivalent resistance of $3 \Omega ?$
(Given resistivities of iron and copper-nickel alloy wire are $12 \;\mu \Omega {cm}$ and $51\; \mu \Omega {cm}$ respectively) (in ${m}$)
To get maximum current through a resistance of $2.5\,\Omega $, one can use $m$ rows of cells, each row having $n$ cells. The internal resistance of each cell is $0.5\,\Omega $. What are the values of $n$ and $m$ if the total number of cells is $45$ ?
Two rods of copper and iron with the same cross-sectional area are joined at $S$ and a steady current $I$ flows through the rods as shown in the figure. Choose the most appropriate representation of charges accumulated near the junction $S$.
In the meter bridge shown, the resistance $X$ has a negative temperature coefficient of resistance. Neglecting the variation in other resistors, when current is passed for some time, in the cirucit, balance point should shift towards.
In the circuit shown in the figure, the switch $S$ is initially open and the capacitor is initially uncharged. $ I_1, I_2$ and $I_3$ represent the current in the resistance $2\,\Omega , 4\,\Omega $ and $8\,\Omega$ respectively.
In a Wheatstone bridge, $P = 90\,\Omega $, $Q = 110\,\Omega $ , $R = 40\,\Omega $ and $S = 60\,\Omega $ and a cell of $4\,V\,emf$. Then the potential difference between the diagonal along which a galvanometer is connected is ............. $V$
A battery of internal resistance $4\, ohm$ is connected to the network of resistance as hown. In the order that the maximum power can be delivered to the network, the value of $R$ in ohm should be :-