Download App

STD 12 - 2. Electric potential and capacitance — NEET STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceNEETSTD 12 - 2. Electric potential and capacitance4 Marks
Question
Two identical parallel plate capacitors of capacitance $C$ each are connected in series with a battery of emf, $E$ as shown below. If one of the capacitors is now filled with a dielectric of dielectric constant $k$, then the amount of charge which will flow through the battery is (neglect internal resistance of the battery)
✓

Answer

(b)

Initially, $\quad C_{ eq }=\frac{C}{2}, V=E$

So, charge that is delivered by cell is

$Q_1=C_{ eq } E=\frac{C E}{2}$

In series charge remains same for both capacitors.

When one of capacitors is filled with a dielectric then,

$C_{ eq }=\frac{k C^2}{(C+k C)}=\left(\frac{k}{1+k}\right) C$

As battery remains connected, $V=E$. So, charge of combination

$Q_2=C_{ eq } V=\left(\frac{k}{1+k}\right) C E$

So, extra charge given by cell after insertion of dielectric is

$\Delta Q=Q_2-Q_1=\left(\frac{k}{1+k}-\frac{1}{2}\right) C E$

$=\frac{k-1}{2(k+1)} \cdot C E$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

NEET STD 11 Science question papers→Gujarat Board STD 11 Science question papers→Gujarat Board question paper generator→

Similar questions

A proton (mass $m$ and charge $+e$) and an $\alpha  -$ particle (mass $4m$ and charge $+2e$) are projected with the same kinetic energy at right angles to the uniform magnetic field. Which one of the following statements will be true
→
A body is imparted motion from rest to move in a straight line. If it is then obstructed by an opposite force, then
→
A mass $m$ is vertically suspended from a spring of negligible mass; the system oscillates with a frequency $n$. What will be the frequency of the system if a mass $4 m$ is suspended from the same spring
→
If voltage across zener diode is $6\, V$ then find out value of maximum resistance in this condition. (in $k \Omega$)
→
Two cars get closer by $8\,m$ every second while travelling in the opposite directions. They get closer by $0.8\,m$ in every second while travelling in the same direction. What are the speeds of the two cars ?
→
$'Torr'$ is the unit of
→
Which alkene is formed from the following reaction

$C{H_3}C{H_2}C{H_2}CH = PP{h_3} + 2 - $  Butanone

→
When the $N-$pole of a bar magnet points towards the south and $S-$pole towards the north, the null points are at the
→
Half life of radioactive element depends upon
→
A railway compartment is lit up by thirteen lamps each taking $2.1\, amp$ at $15\, volts$. The heat generated per second in each lamp will be ............ $cal$
→