A $10\,V$ battery with internal resistance $1\,\Omega $ and a $15\,V$ battery with internal resistance $0.6\,\Omega $ are connected in parallel to a voltmeter (see figure). The reading in the voltmeter will be close to ................ $V$
JEE MAIN 2015, Diffcult
Download our app for free and get startedPlay store
As the two cells oppose each other hence, the effective emf in closed circuit is $15-10=5 \,\mathrm{V}$ and net resistance is $1+$ $0.6=1.6 \,\Omega$ (because in the closed circuit the internal resistance of two cells are in series.

Current in the circuit,

$I=\frac{\text { effective emf }}{\text { total resistance }}=\frac{5}{1.6} \,A$

The potential difference across voltmeter will be same as the terminal voltage of either cell.

Since the current is drawn from the cell of $15 \,\mathrm{V}$

$\therefore \quad V_{1}=E_{1}-I r_{1}$

$=15-\frac{5}{1.6} \times 0.6=13.1 \,\mathrm{V}$

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
    $A$ total charge $Q$ flows across a resistor $R$ during a time interval $= T$ in such a way that the current vs. time graph for $0 \rightarrow T$ is like the loop of a sin curve in the range $0 \rightarrow \pi$ . The total heat generated in the resistor is
    View Solution
  • 2
    In the following $'I'$ refers to current and other symbols have their usual meaning, Choose the option that corresponds to the dimensions of electrical conductivity
    View Solution
  • 3
    A resistor develops $300 \,J$ of thermal energy in $15 \,s$, when a current of $2\, A$ is passed through it. If the current increases to $3 \,A$, the energy developed in $10\,\,s$  is........$J.$
    View Solution
  • 4
    For what value of unknown resistance $X$, the potential difference between $B$ and $D$ will be zero in the circuit shown in the figure ............... $\Omega$
    View Solution
  • 5
    The current $I$ flowing through the given circuit will be $.....A$.
    View Solution
  • 6
    A battery consists of a variable number $n$ of identical cells (having internal resistance reach) which are connected in series. The terminals of the battery are short-circuited and the current $I$ is measured. Which of the graphs shows the correct relationship between $I$ and $n \,?$
    View Solution
  • 7
    Consider a wire having current $10\,A$ having area of crossection $1\,cm^2$. If number of electrons per unit volume is $9 \times 10^{28}\, m^{-3}$. Find the drift velocity of electrons
    View Solution
  • 8
    The heat generated through $2 \,ohm$ and $8\, ohm$ resistances separately, when a condenser of $200\,\mu F$ capacity charged to $200\, V$ is discharged one by one, will be
    View Solution
  • 9
    For a cell, the graph between the potential difference $(V) $ across the terminals of the cell and the current $(I)$ drawn from the cell is shown in the figure. The $e.m.f.$ and the internal resistance of the cell are
    View Solution
  • 10
    In the circuit shown, the resistances are given in ohms and the battery is assumed ideal with $\mathrm{emf}$ equal to $3.0$ $\mathrm{volts}.$ The resistor that dissipates the most power is
    View Solution