MCQ
What will be reading of voltmeter ................. $V$
- ✓$8.4$
- B$20$
- C$6.2$
- D$10.8$
✓
Answer
Correct option: A.
$8.4$
a
From parallel combination of cell,
From parallel combination of cell,
$\Rightarrow \mathrm{E}=\frac{\frac{20}{4}+\frac{6}{3}}{\frac{1}{4}+\frac{1}{3}}=12$ $\mathrm{volt}$ $\Rightarrow \mathrm{r}=\frac{12}{7}$
$\Rightarrow \mathrm{V}=4\left[\frac{12}{4+\frac{12}{7}}\right]=8.4 \mathrm{\,volt}$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
When a coil is moved or rotated relative a fixed magnet then.
Vapour is injected at a uniform rate in a closed veseel which was initially evacuated. The pressure in the vessel:
A capacitor of capacitance $100\ \mu \mathrm{F}$ is charged to a potential of $12 \mathrm{~V}$ and connected to a $6.4 \ \mathrm{mH}$ inductor to produce oscillations. The maximum current in the circuit would be :
→The least distance of distinct vision for a farsighted person is $1\ m$ . The optical power of the lens of his specs which effectively reduces his $LDDV$ to $25\ cm$ , is
→The kinetic energy possessed by a body of mass $m$ moving with a velocity $ v$ is equal to $\frac{1}{2}m{v^2}$, provided
→A resistor $R_1$ dissipates the power P when connected to a certain generator. If the resistor $R_2$ is put in series with $R_1$, the power dissipated by $R_1$
→The electric potential $V(x, y, z)$ for a planar charge distribution is given by:
→$V\left( {x,y,z} \right) = \left\{ {\begin{array}{*{20}{c}}
{0\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,for\,x\, < \, - d}\\
{ - {V_0}{{\left( {1 + \frac{x}{d}} \right)}^2}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,for\, - \,d\, \le x < 0}\\
{ - {V_0}\left( {1 + 2\frac{x}{d}} \right)\,\,\,\,\,\,\,\,\,\,\,for\,0\, \le x < d}\\
{ - 3{V_0}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,for\,x\, > \,d}
\end{array}} \right.$
where $-V_0$ is the potential at the origin and $d$ is a distance. Graph of electric field as a function of position is given as
If $P$ and $Q$ are two batteries connected in series with anode of one connected to anode of the other, producing voltages $E_1$ and $E_2>E_1$ respectively. The e.m.f of the pair is
→To make P type semiconductor in silicon :
In a copper voltameter, mass deposited in 6 minutes is m gram. If the current-time graph for the voltameter is as shown here, then the E.C.E of the copper is
