Question 1 :
Two positive point charges $$q_1$$ and $$q_2$$ are kept at the distance d. If the distance between them is triple. Calculate by which factor new electrostatic force is decreased.<br/>
Question 2 :
A body is brought near to a negatively charged gold leaf electroscope. If the divergence of leaves increases. What is the nature of charge on the body?
Question 3 :
What happens when two straws are individually rubbed with separate sheets of paper and are brought near to each other?
Question 4 :
A positive charge $$q$$ is placed in a spherical cavity made in a positively charged sphere. The centers of sphere and cavity are displaced by a small distance $$\vec {l}$$. Force on charge $$q$$ is:<br>
Question 6 : <span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><p class="wysiwyg-text-align-left">Fill in the blank.</p><p class="wysiwyg-text-align-left">$$1$$ Coulomb of charge contains_______number of electrons.</p>
Question 7 :
Assertion: Gauss's law show diversion when inverse square law is not obeyed.
Reason: Gauss's law is a consequence of conservation of charges.
Question 8 :
A gold leaf electroscope is given a positive charge so that its leaves diverge. How is the divergence of leaves affected, when an uncharged rod is brought near its disc ?
Question 9 :
You are provided with a negatively charged gold leaf electroscope. State and explain what happens when an uncharged metal rod is brought near the disc of electroscope.
Question 12 : <span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><p class="wysiwyg-text-align-left">If the flux of the electric field through a closed surface is zero:</p>
Question 14 : <span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><p class="wysiwyg-text-align-left">If $$10$$ million electrons are removed from a neutral body, then the charge on the body is :</p>
Question 15 :
If the number of electric lines of force emerging out of a closed surface is 1000, then the charge enclosed by the surface is
Question 16 :
State whether true or false :Electric flux through a closed surface is equal to total flux due to all the charges enclosed within that surface only.
Question 17 :
12 positive charges of magnitude q are placed on a circle of radius R in a manner that they are equallyspaced. A charge +Q is placed at the centre. If one of the charges q is removed, then the force on Q is
Question 18 :
The materials that do not allow flow of electron through them are known as :
Question 19 :
An electric line of force in the $$xy-plane$$ is given by equation $$x^{2} + y^{2} = 1$$. A particle with unit positive charge, initially at rest at the point $$x = 1, y = 0$$ in the $$xy - plane$$.
Question 22 :
If $$10^{20}$$ <span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small">electrons are removed from a conductor. The nature and magnitude of the charge developed on it is :
Question 23 :
State whether the given statement is True or False :Conductors when charged transfer all charges to the entire surface of the conductor. 
Question 24 :
A point charge $${q_1} =  - 5.8\mu C$$ is held stationary at the origin . A second point charge $${q_2} =  + 4.3\mu C$$ moves from the point $$(0.26m,0,0)$$ to $$(0.38m,0,0)$$.How much work is done by the electric force on {q_2}.
Question 25 :
The ratio of electric force between two electrons to two protons separated by the same distance in air is
Question 26 :
State whether true or false:<br/>Alcohol and ether are conducting liquids of electricity. <br/>
Question 27 :
The process of charging a conductor from a chargedbody without touching them together is calledinduction
Question 29 :
Deuteron and $$\alpha$$-particle are put $$1{A}^{o}$$ apart in air. Magnitude of intensity of electric field due to deuteron of $$\alpha$$-particle is $$(N/C)$$<b></b>
Question 30 :
A gold leaf electroscope is given a positive charge so that its leaves diverge. How is the divergence of leaves affected, when a negatively charged rod is brought near its disc?
Question 31 :
State whether given statement is True or False :In conductors electric current can flow freely. <br/>
Question 32 :
The process due to which an uncharged body acquires electric charges when held near a charged body is called :<br/>
Question 33 :
A glass rod rubbed with silk is brought near the fur rubbed with an ebonite rod. What will be your observation between them? <br>
Question 34 :
A charge + Q is located in space at the point $$(x=1m,y=10m,z=5m)$$. What is the total electric flux that passes through the yz-plane?
Question 36 : <span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small"><p class="wysiwyg-text-align-left">The electric field due to a charge at a distance of $$3m$$ from it is $$500 N/C$$. The magnitude of the charge is$$\left [ \dfrac{1}{4\pi \varepsilon _{0}}=9\times 10^{9}Nm^{2}/C^{2} \right ]$$ :</p>
Question 37 :
A plane area of $$100\ {cm}^{2}$$ is placed in uniform electric field of $$100\ N/C$$ such that the angle between area vector and electric field is $$60^o$$. The electric flux over the surface is
Question 38 :
The charge on a body is +1 C. Find the number of electrons in excess or deficit on the body.
Question 40 :
Two conducting charged spheres $$X$$ and $$Y$$ having unequal charges are connected by the wire. Which of the following is true?
Question 41 :
Complete the following statements with an appropriate word /term be filled in the blank space(s).<br/>The force of attraction or repulsion between two charges is given by ......................<br/>
Question 42 :
The field due to a charge at a distance $$x$$ from it is $$E$$. When the distance is doubled, the intensity of the field would be:
Question 45 :
The specific charge of a proton is $$\displaystyle 9.6\times { 10 }^{ 7 }C/kg$$. The specific charge of an alpha particle will be:
Question 46 :
Two point charges $$2\ C$$ and $$-6\ C$$ attract each otherwith a force of $$12\ N$$. A negative charge of $$2\ C$$ isadded to each of the above charges, now theforce between them is :
Question 47 :
An uncharged insulator can be charged by ______ with another suitable body.<br/><br/>
Question 48 :
<span class="wysiwyg-font-size-small"><span class="wysiwyg-font-size-small">Another unit for the quantity having the unit $$\dfrac{C^2 }{Nm^2}$$ is:
Question 52 :
When the distance between two charged particles is halved, then the force between them becomes :
Question 53 :
A small, flat coil of resistance $$r$$ is placed at the centre of a large, closed coil of resistance $$R$$. The coils are coplanar and their mutual inductance is $$M$$. Initially, a constant current $$i$$ was flowing in the inner coil. If this current is suddenly switched off, what charge will circulate in the other coil?
Question 54 :
Position vectors of two point charges of $$1nC$$ each are $$(1,1,-1)$$m and $$(2,3,1)$$m respectively. Magnitude of electric force acting between them is ___N.
Question 55 :
Two identical metal spheres possess $$+60\ C$$ and $$-20\ C$$ of charges. They are brought in contact and then separated by $$10\ cm$$. The force between them is:
Question 56 :
If the electric flux entering and leaving an enclosed surface respectively is $$\phi_{1}$$ and $$\phi_{2}$$, the electric charge inside the surface will be
Question 58 :
Find the minimum force between the two electrons around He nucleus. Assume radius of He nucleus $$=$$ 6.8 A$$^o$$.
Question 59 :
$$ 1 \times 10^{-6} C  $$ charge is on a drop of water having mass $$ 10^{-6} \mathrm{kg}  $$ . What electric field should be applied on the drop so that it is in the balanced condition with its weight?<br/>
Question 60 : <table class="table table-bordered"><tbody><tr><td> i. $$\sigma _a$$</td><td> m. $$\dfrac{q_a + q_b}{4 \pi R^2}$$</td></tr><tr><td> ii. $$\sigma_b$$</td><td> n. $$\dfrac{-q_a}{4 \pi a^2}$$</td></tr><tr><td> iii. $$\sigma_R$$</td><td> o. $$\dfrac{-q_b}{4 \pi b^2}$$</td></tr></tbody></table>Match the table.
Question 61 :
Two pith balls each of mass $$1g$$ and carrying a charge 1$$\mu$$C are attached to the ends of silk threads $$1m$$ long, the other ends of which are attached to some fixed point, in a gravity free space. The force between them is :
Question 62 :
An electric dipole is placed at the centre of a sphere. Mark the correct options :
Question 63 :
A charge $$q$$ is enclosed in a cube. What is the electric flux associated with one of the faces of cube ?<br/>
Question 64 :
The radius of hollow metallic sphere is r If the potential difference between its surface and a at a distance 3r from its centre is v then the electric field intensity at a distance of 3r its centre is:
Question 65 :
The magnitude of the electric field on the surface of a sphere of radius $$r$$ having a uniform surface charge density $$\sigma$$ is
Question 66 :
A charge q is placed at the centre of the line joining two equal charges Q. The system of the three charges will be in equilibrium if q is equal to :<br/>
Question 67 :
A system consists of a uniformly charged sphere of radius $$R$$ and a surrounding medium filled by a charge with the volume density $$\quad \rho =\cfrac { \alpha }{ r } $$, where $$\alpha$$ is a positive constant and $$r$$ is the distance from the centre of the sphere. Find the charge of the sphere for which the electric field intensity $$E$$ outside the sphere is independent of $$R$$.
Question 68 : <p>Two bodies X and Y carry charges $$ - 6.6\mu C$$  and $$ - 5\mu C$$.How many electrons should be transferred from X and Yso that they acquire equal charges?</p>
Question 69 :
If the net charge enclosed by a closed Gaussian surface is zero, does this mean that the electric field at all points on the surface is also zero?
Question 71 :
The electric force acting between two point charges kept at a certain distance in vacuum is $$16$$N. If the same two charges are kept at the same distance in a medium of dielectric constant $$8$$. The electric force acting between them is __________N.
Question 72 :
12 positive charges of magnitude q are placed on a circleof radius R in a manner that they are equally spaced. Acharge +Q is placed at the centre. If one of the chargesq is removed, then the force on Q is:
Question 73 :
An electric dipole is placed in an electric field generated by a point charge. Then
Question 74 :
When a plastic comb rubbed on hair is brought near bits of paper, it attracts them because:
Question 75 :
Three charged particles are in equilibrium under their electrostatic forces only:<br>
Question 76 :
$$n$$ number of identical spherical droplets, each having surface charge density $$\sigma $$ coalesce to form a bigger drop of surface charge density
Question 77 :
A parallel plate capacitor is made of two circular plates separated by a distance of $$5\ mm$$ and with a dielectric of dielectric constant $$2.2$$ between them. When the electric field in the dielectric field in the dielectric is $$3 \times 10^4\ V/m$$, the charge density of the positive plate will be close to :
Question 78 :
What is the total electric flux leaving the surface of the sphere?
Question 79 :
The total number of lines of induction leaving a closed surface normally is called<br>
Question 80 :
When a glass rod is rubbed with silk, both become charged due to:
Question 81 :
State whether the given statement is True or False :When silk is rubbed with glass, the silk gets positively charged.
Question 82 :
Two thin infinite parallel sheets have uniform surface densities of charge $$+\sigma$$ and $$-\sigma$$. Electric field in the space between the two sheets is :
Question 83 :
Relative permittivity of water is $$81$$. If $$\epsilon_{w}$$ and $$\epsilon_{0}$$ are permittivities of water and vacuum respectively, then :
Question 84 :
In a regular polygon of $$n$$ sides, each corner is at a distance $$r$$ from the centre. Identical charges of magnitude $$q$$ are placed at $$(n-1)$$ corners. The field at the centre is
Question 85 : <p class="wysiwyg-text-align-left">A charge of $$1\mu C$$ is divided into two parts such that their charges are in the ratio of $$2 : 3$$. These two charges are kept at a distance 1m apart in vaccum. Then, the electric force between them (in newton) is :<br/></p>
Question 86 :
State whether the given statement is True or False :Gauss's law implies that the total electric flux through a closed surface is zero if no charge is enclosed by the surface.
Question 87 :
If there is only one type of charge in the universe, then what is the flux to the entire universe.<br/>($$\vec { E } \rightarrow $$ Electric field, $$\vec { ds } \rightarrow $$ Area vector)
Question 88 :
The force acting between two opposite charges of equal magnitude is F. If $$25\%$$ charges are transferred from one to another, the force acting between them will be____.
Question 90 :
The electrostatic force between two point charges $$q_{1}$$ and $$q_{2}$$ at separation 'r' is given by $$F = \dfrac {Kq_{1}q_{2}}{r^{2}}$$. The constant K:
Question 91 :
If the electric flux entering and leaving an enclosed surface respectively are $$\phi_1$$ and $$\phi_2$$, the electric charge inside the surface will be :
Question 92 :
$$A$$ and $$B$$ are two points on the axis and the perpendicular bisector respectively of an electric dipole. $$A$$ and $$B$$ are far away from the dipole and at equal distance from it. The field at $$A$$ and $$B$$ are $$\vec{E}_{A}$$ and $$\vec{E}_{B}$$.<br>
Question 94 : <p class="wysiwyg-text-align-left">Two charges $$Q_{1}$$ and $$Q_{2}$$ are placed in vacuum at a distance d and the force acting between them is $$5$$ units. If a medium of dielectric constant $$2$$ is introduced around them, the net force now will be :<br/></p>
Question 95 :
A glass rod when rubbed with silk cloth, acquires a charge of $$1.6\times 10^{-11}C$$, then the charge on silk cloth will be:
Question 96 :
Assertion: A charged particle free to move in an electric field always move along an electric line of force.
Reason: The electric lines of force diverge from positive charge and converge at a negative charge.
Question 97 :
If the flux of the electric field through a closed surface is zero, then :
Question 98 :
A spherical shell of radius $$R$$ has a change $$+q$$ units. The electric field due to the shell at a point
Question 99 :
An $$\alpha$$ particle is situated in an electric field of strength $$15\times {10}^{4}N{C}^{-1}$$. Force acting on it is
Question 101 :
Find the electric field at a distance $$x$$ from the centreinside the shell.
Question 102 :
The electric field at a point $$2$$cm from an infinite line charge of linear charge density $$10^{-7}$$ $$cm^{-1}$$ is?
Question 103 :
Two thin rods of length L lie along x-axis, one between $$\displaystyle x = \frac{a}{2}  \ \ \   to   \ \ \ \ \ x = \frac{a}{2} + L$$ and the other between $$x = \displaystyle -\frac{a}{2}  to  \ \ \ \ \ x = - \frac{a}{2} - L$$.<br/>Each rod has positive charge Q distributed uniformly along the length. Find the magnitude of the force which one rod exerts on the other.
Question 104 :
Charges $$Q_1$$ and $$Q_2$$ lie inside and outside respectively of a closed surface S. Let E be the field at anypoint on S and $$\phi$$be the flux of E over S
Question 105 :
The expression for electric field intensity at a point outside uniformly charged thin place sheet is (d is the distance of point from plane sheet)
Question 106 :
Using general logic for electric field, the flux of $$\overrightarrow{g}$$ through any closed surface is given by :
Question 107 :
A long cylindrical wire carries a linear charge density of $$3\times 10^{-8} Cm^{-1}$$. An electron revolve around it in a circular path under the influence of the attractive force. $$KE$$ of the electron is :
Question 108 :
Let $$E_1(r), E_2(r)$$ and $$E_3(r)$$ be the respective electric fields at a distance r from a point charge Q, an infinitely long wire with constant linear charge density $$\lambda$$, and an infinite plane with uniform surface charge density $$ \sigma $$. lf $$E_1(r_0) = E_2(r_0) = E_3(r_0)$$ at a given distance $$r_0$$, then :<br/>
Question 109 :
The electric field in a region is $$E = \displaystyle \frac{5\times 10^3 x}{2}\hat{i} \ NC^{-1} cm^{-1} $$. The charge contained inside a cubical volume bounded by the surfaces $$x = 0, x = 1, y = 0, y = 1, z = 0, z = 1$$ is (where x, y, z are in cm) :
Question 110 :
The electric field in a region is radially outward with magnitude $$E=\alpha r$$. Calculate the charge contained in a sphere of radius R centered at the origin. Calculate the value of the charge if $$\alpha =100 Vm^{-2}$$ and R=0.30 m.
Question 111 :
The radii of two conducting sphere are $$ a $$ and $$ b $$. They are charged by equal charge density. What would be the ratio of the electric field intensities at their surface?
Question 112 :
The total electric flux through a closed surface is equal to
Question 113 :
Let there be a spherically symmetric charge distribution with charge density varying as $$\displaystyle \mathrm{p}(\mathrm{r})=\mathrm{p}_{0}(\frac{5}{4}-\frac{\mathrm{r}}{\mathrm{R}})$$ upto $$\mathrm{r}=\mathrm{R}$$, and $$\mathrm{p}(\mathrm{r})=0$$ for $$\mathrm{r}>\mathrm{R}$$, where $$\mathrm{r}$$ is the distance from the origin. The electric field at a distance $$\mathrm{r}(\mathrm{r}<\mathrm{R})$$ from the origin is given by :<br/>
Question 114 :
Two infinitely long parallel conducting plates having surface charge densities$$\displaystyle +\sigma$$ and$$\displaystyle -\sigma$$respectively, are separated by a small distance. The medium between the plates is vacuum. If$$\displaystyle { \varepsilon }_{ 0 }$$is the dielectric permittivity of vacuum then the electric field in the region between the plates is:
Question 115 :
A solid sphere of radius $$R$$ has a charge $$Q$$ distributed in its volume with a charge density $$\rho =\kappa { r }^{ a }$$, where $$\kappa$$ and $$a$$ are constants and $$r$$ is the distance from its centre.<br>If the electric field at $$r=\cfrac{R}{8}$$ is $$\cfrac{1}{8}$$ times that at $$r=R$$, find the value of $$a$$ .
Question 116 :
Let a total charge $$2Q$$ be distributed in a sphere of radius $$R$$, with the charge density given by $$\rho(r) = kr$$, where $$r$$ is the distance from the centre. Two charges $$A$$ and $$B$$, of $$-Q$$ each, are placed on diametrically opposite points, at equal distance, a form the centre. If $$A$$ and $$B$$ do not experience any force, then:
Question 117 :
Consider a uniform electric field $$E=3\times 10^3 \hat i \: N/C$$. What is the flux of this field through a square of $$10\  cm$$ on a side whose plane is parallel to the yz plane?
Question 118 :
A spherically symmetric charge distribution is characterised by a charge density having the following variation :<br>$$p(r)=p_o(1-\frac {r}{R})$$ for $$r<R$$<br>$$p(r)=0$$ for $$r\geqslant R$$<br>Where r is the distance from the centre of the charge distribution and $$p_o$$ is a constant. The electric field at an internal point (r<R) is :
Question 119 :
A point charge +q is placed at the centre of a cube of side L. The electric flux emerging from the cube is-
Question 120 :
The electric field $$0.50 m$$ from a small sphere with a positive charge of $$7.2\times 10^{5} C$$ is
Question 121 :
The magnitude of the electric field as a function of the distanee r outside the ball is given by :
Question 122 :
A ball of radius R carries a positive charge whose volume charge density depends only on the distance r from the ball's centre as: $$\rho=\rho_0(1-\dfrac {r}{R})$$ where $$\rho_0$$ is constant. Assume $$\epsilon$$ as the permittivity of the ball.<br/>Then the magnitude of the electric field as a function of the distance r outside the ball is given by :
Question 123 :
A system consists of a thin charged wire ring of radius r and a very long uniformly charged wire oriented along the axis of the ring, with one of its ends coinciding with the center of the ring. The total charge on the ring is q, and the linear charge density on the straight wire is $$\lambda$$. The interaction force between the ring and the wire is :
Question 124 :
In a region, the intensity of an electric field is given by $$E = 2i + 3j + k$$ in $$NC^{-1}$$. The electric flux through a surface $$S = 10i \ m^{2}$$ in the region is:
Question 126 :
Charges Q, 2Q and 4Q are uniformly distributed in three dielectric solid spheres 1,2 and 3 of radii R/2,R and 2R respectively. If magnitudes of the electric fields at point P at a distance R from the centre of sphere 1, 2 and 3 are $$E_1$$, $$E_2$$ and $$E_3$$ respectively, then :<br/>
Question 127 :
Assertion: STATEMENT-1 : In a region where uniform electric field exists, the net charge within volume of any size is zero.
Reason: STATEMENT-2 : The electric flux within any closed surface in a region of uniform electric field is zero.
Question 128 :
The value of distance $$r_m$$ at which electric field intensity is maximum, is given by :
Question 129 :
Fill in the blanks.<br/>A field normal to the plane of a circular wire n turns and radius r which carries a current I is measured on the axis of the coil at small h distance h from the centre of the coil. This is smaller than the field at the centre by a friction ____
Question 130 :
Electric flux through a surface of area $$100\ m^{2}$$ lying in the xy plane is (in V-m) if $$\vec{E}=\hat{i}+\sqrt{2}\hat{j}+\sqrt{3\hat{k}}$$<br/>
Question 133 :
The magnitude of electric field as a function of the distance r inside the sphere is given by :
Question 134 :
A semi-circular rod of radius $$R$$ is charged uniformly with a total charge $$Q\ C$$. The electric field intensity at the centre of the curvature is<br/>(where $$K= \dfrac{1}{4 \pi \epsilon_0}$$)<br/>
Question 135 :
Charges $$Q_1$$   and  $$Q_2$$ lie inside and outside, respectively, of a closed surface S. Let E be the field at any point on S and $$\phi$$ be the flux of E over S.
Question 136 :
The ratio of the energy required to set up in cube of side 10 cm uniform magnetic field of 4$${ Wb/m }^{ 2 }$$ and a uniform electric field of $$10^{ 6 }V/m$$ is:
Question 137 :
The value of distance $$r_m$$, inside the ball at which electric field intensity maximum is given by-
Question 138 :
Mathematically, electric flux can $$\phi$$be represented as:<br><br>$$\vec E =$$ electric field<br>$$\hat n=$$ surface normal vector<br>$$A=$$ surface area
Question 139 :
A point charge $$q$$ is placed at a point on the axis of a non-conducting circular plate of radius $$r$$ at a distance $$R (R >> r)$$ from its center. The electric flux associated with the plate is :<br/>
Question 140 :
A charge $$Q$$is located at the centre of a sphere of radius $$R$$. Calculate the flux going out through the surfaceof the sphere.
Question 141 :
Let E$$_1$$(r), E$$_2$$(r) and E$$_3$$(r) be the respective electric fields at a distance r from a point charge Q, an infinitely long wire with constant linear charge density $$\lambda$$, and an infinite plane with uniform surface charge density $$\sigma$$. If E$$_1(r_0) = E_2 (r_0) = E_3 (r_0)$$ at a given distance r$$_0$$, then :
Question 142 :
An electric charge $$q$$is placed at the centre of a cube of side $$a$$ The electric flux throughone of its faces is
Question 143 :
A point charge $$q$$ is situated at a distance $$r$$ on axis from one end of a thin conducting rod of length $$L$$ having a charge $$Q$$ (Uniformly distributed along its length). The magnitude electric force between the two is _______
Question 144 :
Eight dipoles of charges of magnitude $$q$$ are placed inside a cube. Then, the total electric flux coming out of the cube will be
Question 145 :
Two charged spheres having radii a and b are joined with a wire then the ratio of electric field $$\dfrac{E_a}{E_b}$$ on their surface is?
Question 146 :
Compute the electric flux through a square surface of edges $$2l$$due to a charge $$+Q$$ whose geometric centre islocated on the x-axis at a perpendicular distance $$l$$ from the centre of the square.
Question 147 :
A solid sphere of radius $$R$$ has a charge $$Q$$ distributed in its volume with a charge density $$\rho = kr^{a}$$, where $$k$$ and $$a$$ are constants and $$r$$ is the distance from its centre. If the electric field at $$r = \dfrac {R}{2}$$ is $$\dfrac {1}{8}$$ times that at $$r = R$$, the value of $$a$$ is
Question 148 :
Given a uniform electric field $$E=5 \times 10^3\hat i N/C$$. Find the flux of this field through a square of side $$10cm$$ on a side whose plane is parallel to YZ-plane :
Question 149 :
Charges $$Q_1$$ and $$Q_2$$ lie inside and outside respectively of a closed surface S. Let E be the field at any point on S and $$\phi$$ be the flux of E over S.
Question 150 :
Charges Q, 2Q and 4Q are uniformly distributed in three dielectric solid spheres 1, 2 and 3 of radii R/2, R and 2R respectively. If magnitudes of the electric fields at point P at a distance R from the centre of spheres 1, 2 and 3 are $$E_1, E_2,$$ and $$ E_3$$ respectively, then:<br/>
