Question 1 :
State whether the given statement is True or False :A small isolated conductor has a large positive charge. The electric field inside this conductor will be zero.<br/>

Question 2 :
A conducting sphere of radius R is given a charge Q. The electric potential and the electric field at the centreof the sphere respectively are :

Question 3 :
The plates of a parallel plate condenser are pulled apart with a velocity v. If at any instant their mutual distance of separation is x, the magnitude of the time of rate of change of capacity depends on x as follows :

Question 4 :
A parallel plate capacitor is made by stacking $n$ equally spaced plates connected alternatively. If the capacitance between any two adjacent plates is $C$, then the resultant capacitance is-

Question 5 :
Two spheres of radii $3$cm and $5$cm are charged to potentials $3000$V and $4500$V respectively. They are then connected by a thin metallic wires. The loss of electric energy in this process is?

Question 6 :
<span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><p class="wysiwyg-text-align-left">A charge $q$ of mass $m$ is released with a velocity $1\times 10^{6}\ m/s$ from a large distance from a fixed positive charge $Q$. The closest distance of approach is:</p>

Question 7 :
A highly conducting sheet of aluminium foil of negligible thickness is placed between the plates of a parallel plate capacitor. The foil is parallel to the plates at distance $\dfrac{d}{2}$ from positive plate where $d$ is distance between plates. If the capacitance before the insertion of foil was $10 \; \mu F$ , its value after the insertion of foil will be:

Question 8 :
Two positively charged particles $X$ and $Y$ are initially far away from each other and at rest. $X$ begins to move towards $Y$ with some initial velocity. The total momentum and energy of the system are $p$ and $E$.Then:<br/>

Question 9 :
A capacitor has a capacitance of $27.0 microfarads$.<br>If we triple the area of the plates of the capacitance and cut the distance between the plates to $1/3$ of its original value, what is the new capacitance of the capacitor?

Question 10 :
A solid conducting sphere having a charge Q is surrounded by an uncharged concentric conducting hollow spherical shell. Let the potential difference between the surface of the solid sphere and that of the outer surface of the hollow shell be V. If the shell is now given a charge of $-3$Q, the new potential difference between the same two surface is :

Question 11 :
Two point charges $q$ and $q_1$ are placed at distance $r$ apart. A dielectric sheet of dielectric constant $k$ and thickness $t$ is placed in between. Find the force between the two charges :<br/>

Question 12 :
If a slab of insulating material $4\times 10^{-5}m$ thick is introduced between the plates of a parallel plate capacitor, the distance between the plates has to be increased by $3.5\times 10^{-5}m$ to restore the capacity to original value. Then the dielectric constant of the material of slab is :<br/>

Question 14 :
A parallel plate air capacitor is charged to a potential difference of V volts. After disconnecting the charging battery the distance between the plates of the capacitor is increased using an insulating handle. As a result the potential difference between the plates:

Question 15 :
Where should $q_3$ be placed to make the 'potential energy of the system equal to zero ?

Question 16 :
<span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><p class="wysiwyg-text-align-left">Calculate the electrostatic potential energy of anelectron-proton system of hydrogen atom. In thefirst Bohr orbit of hydrogen atom, the radius ofthe orbit is $5.3\times 10^{-11}m\ $:</p>

Question 17 :
A parallel plate capacitor, filled with a material of dielectric constant $K$, is charged to a certain voltage and is isolated. The dielectric material is removed. Then: &#160; &#160; &#160;&#160;<span class="wysiwyg-font-size-small"><b><br/></b>(a) capacitance decreases by a factor $K$<br/>(b) electric field reduces by a factor $K$<span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><br/>(c) voltage across the capacitor increases by a factor $K$<span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><br/>(d) &#160;charge stored in the capacitor increases by a factor $K$<p></p><p></p>

Question 18 :
A capacitor has some dielectric between its plates, and the capacitor is connected to a dc source. The battery is now disconnected and then the dielectric is removed, then

Question 19 :
A photographic flash unit consists of a xenon-filled tube. It gives a flash of average power $2000W$ for $0.04s$. The flash due to discharge of a fully charged capacitor of $40\mu F$. The voltage to which it is charged before a flash is given by the unit is :<br/>

Question 20 :
Surface charge density of a sphare of a radius $10 cm$ is $8.85 \times {10^{ - 8}}c/{m^2}.$ Potential at the centre of the sphare is

Question 21 :
A Parallel platecapacitor made of circular plates each of radius $R=6.0cm$ has a capacitance 100$\mathrm { pF }$&#160;is connected to 230$\mathrm { V }$ of $\mathrm { AC }$ supply&#160;of 300 rad/sec.frequency. The rms value of displacement current

Question 22 :
A parallel plate capacitor has plate area $A$, plate separation $d$, and magnitude of charge, $Q$, on each plate. The capacitor is isolated from any voltage source. The plates of this capacitor are then separated to a new distance, $1.5d$.<br>In terms of the given variables and fundamental constants, how much work was required by an outside force to separate the plates?

Question 23 :
A simple pendulum of mass m charged negatively to q coulomb oscillates with a time period T in a downward electric field E such that mg &gt; qE. If the electric field is withdrawn, the new time period :<br/>

Question 24 :
When the separation between the two charges is increased the electric potential energy of the charges

Question 25 :
A&#160;parallel plate capacitor has area $20 cm^2$&#160;and&#160;separation between&#160;the plates is $0.1 mm$. The dielectric break down&#160;strength&#160;is $\displaystyle 3\times 10^6$ <br> $v/m$. The&#160;maximum r.m.s voltage&#160;which&#160;can be safely applied is :<br/>

Question 26 :
When dielectric medium of constant k is filled between the plates of a charged parallel-plate condenser, then the energy stored becomes, as compared to its previous value,

Question 27 :
Three condenser of capacity $2\mu F, 4\mu F$ and $8 \mu F$ respectively, are first connected in series and then connected in parallel. The ratio of equivalent capacitances in two cases will be :

Question 28 :
An Uncharged capacitor of capacitance $C$ is connected to a battery of emf&#160; $\varepsilon $ at&#160; $ t=0$ through a resistance $R$, then &#160;<br/>(i) the maximum rate at which energy is stored in the capacitor is:<br/>

Question 29 :
An oil condenser has a capacity of $100\; \mu F$ . The oil has dielectric constant 2. When the oil leaks out ,&#160;its new capacity is :<br/>

Question 30 :
A capacitor of capacitance $C$ is initially charged to a potential difference of $V$ volt. Now it is connected to a battery of $2V$ volt with opposite polarity. The ratio of heat generated to the final energy stored in the capacitor will be :<br>

Question 31 :
Two points P and Q are maintained at potentials of of $10V$ and $-4V$ respectively. The work done in moving $100$ electrons from P to Q is proportional to

Question 32 :
Given that $E = ((3x^2<br><br> + y) \hat i+ x \hat y) kV/m$,find the work done in moving a $- 2 \mu C$ charge from $(0, 5, 0)$ to $(2, -1 , 0)$ by taking the path:<br>$y=5-3x$

Question 34 :
Assertion: If three capacitors of capacitance $C_1 < C_2 < C_3$ are connected in parallel then their equivalent capacitance $C_{parallel} > C_{series}$ Reason: $\dfrac {1}{C_{parallel}}=\dfrac {1}{C_1}+\dfrac {1}{C_2}+\dfrac {1}{C_3}$

Question 35 :
A uniformly charged solid sphere or radius $R$ has potential ${V}_{0}$ (measured with respect to $\infty$) on its surface. For this sphere the equipotential surfaces with potentials $\cfrac { 3{ V }_{ 0 } }{ 2 } ,\cfrac { { 5V }_{ 0 } }{ 4 } ,\cfrac { 3{ V }_{ 0 } }{ 4 } ,\cfrac { { V }_{ 0 } }{ 4 } $ have radius ${R}_{1},{R}_{2},{R}_{3}$ and ${R}_{4}$ respectively. Then