1638 + Interview Questions in ELECTROSTATICS IN GENERAL AWARENESS Page 15 InterviewSolution

701.	How does a torque affect the dipole in an electric field ?
Answer» Torque tries to align the dipole along the field.

Discussion

702.	Which rule gives you the direction of torque ?
Answer» The direction fo torque is given by right hand screw rule.

Discussion

703.	At what points, dipole field intensity is parallel to the line joining the charges ?
Answer» At any point on axial line or equatorial line of dipole.

Discussion

704.	Will an electric dipole have translational motion when placed in a non -uniform electric field? Give reason for your answer.
Answer» Yes, in a non-uniform electric field, an electric dipole experiences unequal forces at its ends. The two forces,add up to give a resulatant force. Which gives a translatroy motion to the dipole.

Discussion

705.	What happens when an electirc dipole is held in a non uniform electric field ?
Answer» It experiences some net force and some net torque.

Discussion

706.	When is the torque on a dipole in a field maximum ?
Answer» Torque is maximum when dipole is held perpendicular to the field.

Discussion

707.	When does an electric dipole placed in a non-uniform electirc field experience a zero torque but non-zero force.
Answer» When the diople is held perpendicular to the field.

Discussion

708.	An electric dipole is placed at an angle of `30^@` to a non-uniform electric field. The dipole will experienceA. a torque onlyB. a translational force only in the disrection of the fieldC. a translational force only in a direction normal tot the dircetion of the fieldD. a torque as well as a translation force .
Answer» Correct Answer - D The dipole will have some distance along the elec. tric field , so , option (1) is correct .

Discussion

709.	Why a small voltage can produce a reasonably large electric field?
Answer» 1. Electric field produced depends upon voltage as well as separation distance. 2. Electric field varies linearly with voltage and inversely with distance. 3. Hence, even if voltage is small, it can produce a reasonable large electric field when the gap between the electrode is reduced significantly.

709.

Why a small voltage can produce a reasonably large electric field?

Answer»

1. Electric field produced depends upon voltage as well as separation distance.

2. Electric field varies linearly with voltage and inversely with distance.

3. Hence, even if voltage is small, it can produce a reasonable large electric field when the gap between the electrode is reduced significantly.

Discussion

710.	Lines of force are imaginary; can they have any practical use?
Answer» Yes, electric lines of force help us to visualise the nature of electric field in a region.

Discussion

711.	The surface charge density of Earth is σ = -1.33 nC/m2. That is about 8.3 × 109 electrons per square metre. If that is the case why don’t we feel it?
Answer» The Earth along with its atmosphere acts as a neutral system. The atmosphere (ionosphere in particular) has nearly equal and opposite charge. As a result, there exists a mechanism to replenish electric charges in the form of continual thunderstorms and lightning that occurs in different parts of the globe. This makes average charge on surface of the Earth as zero at any given time instant. Hence, we do not feel it.

711.

The surface charge density of Earth is σ = -1.33 nC/m2. That is about 8.3 × 109 electrons per square metre. If that is the case why don’t we feel it?

Answer»

The Earth along with its atmosphere acts as a neutral system. The atmosphere (ionosphere in particular) has nearly equal and opposite charge.

As a result, there exists a mechanism to replenish electric charges in the form of continual thunderstorms and lightning that occurs in different parts of the globe. This makes average charge on surface of the Earth as zero at any given time instant. Hence, we do not feel it.

Discussion

712.	Define point charge. Which law explains the interaction between charges at rest?
Answer» 1. A point charge is a charge whose dimensions are negligibly small compared to its distance from another bodies. 2. Coulomb’s law explains the interaction between charges at rest.

712.

Define point charge. Which law explains the interaction between charges at rest?

Answer»

1. A point charge is a charge whose dimensions are negligibly small compared to its distance from another bodies.

2. Coulomb’s law explains the interaction between charges at rest.

Discussion

713.	The force between two charges 0.06m apart is 5N. If each charge is moved towards the other by 0.04 m, then the force between them will becomeA. 7.20 NB. 11.25 NC. 22.50 ND. 45.00 N
Answer» Correct Answer - B

Discussion

714.	A point charge q is rotating around a charge Q in a circle of radius r. The workdone on it by the coulomb force is(a) 2πrq (b) 2πQq (c) \(\frac {Q}{2ε^0r}\) (d) zero
Answer» Correct answer is (d) zero

Discussion

715.	The capacitor C of a spherical conductor of radius R is proportional to(a) R2(b) R(c) R-1(d) R0
Answer» Correct answer is (b) R

Discussion

716.	The electric field due to a dipole at a distance r from its centre is proportional to(a)\(\frac {1}{r^\frac{3}{2}}\)(b)\(\frac {1}{r^3}\)(c)\(\frac {1}{r}\)(d) \(\frac {1}{r^3}\)
Answer» correct answer is (b)\(\frac {1}{r^3}\)

Discussion

717.	If n identical capacitors are connected in series and then in parallel then the ratio of effective capacity in parallel and in series combination i.e. `C_(P)/C_(S)` isA. nB. `1//n`C. `n^(2)`D. `1//n^(2)`
Answer» Correct Answer - C `C_(P)=n^(2)C_(S)` `C_(P)/C_(S)=n^(2)`

Discussion

718.	Two identical capacitors are first connected in series and then in parallel. The difference between their effective capacities is `3muF`. The capacity of each capacitor isA. `3muF`B. `4muE`C. `2muF`D. `5muE`
Answer» Correct Answer - C `C_(P)-C_(S)=3` `2C-C/2=3` `(4C-C)/2=3` 3C = 6 `C=2muF`

Discussion

719.	Define ‘Electric dipole'
Answer» Two equal and opposite charges separated by a small distance constitute an electric dipole.

Discussion

720.	The electric field lines never intersect. Justify.
Answer» As a consequence, if some charge is placed in the intersection point, then it has to move in two different directions at the same time, which is physically impossible. Hence, electric field lines do not intersect

Discussion

721.	What is mean by ‘Electric field lines’?
Answer» Electric field vectors are visualized by the concept of electric field lines. They form a set of continuous lines which are the visual representation of the electric field in some region of space.

Discussion

722.	Assertion: Charge is quantized. Reason: Charge, which is less than 1 C is not possible.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. (b) If both assertion and reason are true but the reason is not correct explanation of the assertion. (c) If assertion is true but reason is false. (d) If the assertion and reason both are false. (e) If assertion is false but reason is true.
Answer» (c) If assertion is true but reason is false. Explanation: Q = ±ne and charge lesser than 1 C is possible.

722.

Assertion: Charge is quantized. Reason: Charge, which is less than 1 C is not possible.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. (b) If both assertion and reason are true but the reason is not correct explanation of the assertion. (c) If assertion is true but reason is false. (d) If the assertion and reason both are false. (e) If assertion is false but reason is true.

Answer»

(c) If assertion is true but reason is false.

Explanation: Q = ±ne and charge lesser than 1 C is possible.

Discussion

723.	Assertion: Electric lines of force cross each other. Reason: Electric field at a point supermpose to give one resultant electric field.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. (b) If both assertion and reason are true but the reason is not correct explanation of the assertion. (c) If assertion is true but reason is false. (d) If the assertion and reason both are false. (e) If assertion is false but reason is true.
Answer» (e) Both assertion and reason are true but the reason is not correct explanation of the assertion. Explanation: If electric lines of forces cross each other, then the electric field at the point of intersection will have two direction simultaneously which is not possible physically.

723.

Assertion: Electric lines of force cross each other. Reason: Electric field at a point supermpose to give one resultant electric field.(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. (b) If both assertion and reason are true but the reason is not correct explanation of the assertion. (c) If assertion is true but reason is false. (d) If the assertion and reason both are false. (e) If assertion is false but reason is true.

Answer»

(e) Both assertion and reason are true but the reason is not correct explanation of the assertion.

Explanation: If electric lines of forces cross each other, then the electric field at the point of intersection will have two direction simultaneously which is not possible physically.

Discussion

724.	Electric field at a point is measued in terms of …………
Answer» Electric field at a point is measued in terms of electric field intensity

Discussion

725.	The charge density in maximum at …………
Answer» The charge density in maximum at pointed

Discussion

726.	At a large distance (r), the electric field due to a dipole varies as(a) \(\frac {1}{r}\)(b) \(\frac {1}{r^2}\)(c) \(\frac {1}{r^3}\) (d) \(\frac {1}{r^4}\)
Answer» Correct answer is (c) \(\frac{1}{r^3}\)

Discussion

727.	The workdone in carrying a charge Q, once round a circle of radius R with a charge Q at the centre is-(a) \(\frac {Q_1Q_2}{4πε_0 R^2}\)(b) Zero(c) \(\frac {Q_1Q_2}{4πε_0 R}\)(d) infinite
Answer» (b) zero The electric field is conservative. Therefore, no work is done in moving a charge around a closed path in a electric field.

727.

The workdone in carrying a charge Q, once round a circle of radius R with a charge Q at the centre is-(a) \(\frac {Q_1Q_2}{4πε_0 R^2}\)(b) Zero(c) \(\frac {Q_1Q_2}{4πε_0 R}\)(d) infinite

Answer»

(b) zero

The electric field is conservative. Therefore, no work is done in moving a charge around a closed path in a electric field.

Discussion

728.	A tiny spherical oil drop carrying a net charge q is balanced in still air with a vertical uniform electric field of strength `(81pi)/(7)xx10^5Vm^-1`. When the field is switched off, the drop is observed to fall with terminal velocity `2xx10^-3ms^-1`. Given `g=9.8ms^-2`, viscoisty of the air `=1.8xx10^-5Nsm^-2` and the denisty of oil `=900kg m^-3`, the magnitude of q isA. ` 1. 6 xx 10 ^(19) C`B. ` 3 .2 xx 10^(19) C`C. ` 4.8 xx 10^(19) C`D. ` 8. 0 xx 10^(19) C`
Answer» Correct Answer - D Terminal veloity `v` is given by `6 pi etar v = mg - (( 4 pi r^2)/3) rho g` substituting the values of `eta , v, rho ` and g, we get `r= 3/7 xx 10 ^(-5) 10^(-5) m`. The oil drop will be balanced in air of `qE = mg = ((4 pir^@)/3 ) rho g` Susetiuting the values of `E, r, rho` and g, we get `q= 8. 0 xx 10^(19) C`.

Discussion

729.	Capacitor is a device to store …………
Answer» Capacitor is a device to store charge

Discussion

730.	The process of isolating a certain region of space from external field is called ………
Answer» The process of isolating a certain region of space from external field is called electrostatic shielding

Discussion

731.	Two plates are 1 cm apart and the potential difference between them is 10 V. The electric field between the plates is (a) 10 NC-1 (b) 250 NC-1(c) 500 NC-1(d) 1000 NC-1
Answer» Correct answer is (d) 1000 NC^-1 Hint : E = \(\frac{V}{d}\) = \(\frac {10}{1 \times 10^{-2}}\) = 8.3 x 10² NC^-1

731.

Two plates are 1 cm apart and the potential difference between them is 10 V. The electric field between the plates is (a) 10 NC-1 (b) 250 NC-1(c) 500 NC-1(d) 1000 NC-1

Answer»

Correct answer is (d) 1000 NC^-1

Hint :

E = \(\frac{V}{d}\) = \(\frac {10}{1 \times 10^{-2}}\) = 8.3 x 10² NC^-1

Discussion

732.	The space around the test charge, in which it experiences a force is known as field …………
Answer» The space around the test charge, in which it experiences a force is known as field electric

Discussion

733.	Two plates are 2 cm apart. If a potential difference of 10 V is applied between them. The electric field between the plates will be(a) 20 NC-1 (b) 500 NC-1 (c) 5 NC-1 (d) 250 NC-1
Answer» Answer : 500 NC^-1 Given : x = 2 cm V = 10V E = ? Solution : We know that , E = V/x = 10/2 × 10^-2 = 5 × 10² = 500 NC^-1 ^{\(\therefore\)}The electric field will be 500 NC^-1 (b) 500 NC^-1 \(\frac {V}{d}\)= \(\frac{10}{2 \times 10^{-2}}\) = 500 NC^-1

733.

Two plates are 2 cm apart. If a potential difference of 10 V is applied between them. The electric field between the plates will be(a) 20 NC-1 (b) 500 NC-1 (c) 5 NC-1 (d) 250 NC-1

Answer»

Answer : 500 NC^-1

Given : x = 2 cm

V = 10V

E = ?

Solution : We know that ,

E = V/x

= 10/2 × 10^-2

= 5 × 10²

= 500 NC^-1

^{\(\therefore\)}The electric field will be 500 NC^-1

(b) 500 NC^-1

\(\frac {V}{d}\)= \(\frac{10}{2 \times 10^{-2}}\) = 500 NC^-1

Discussion

734.	The unit of electric field in tensity is …………
Answer» The unit of electric field in tensity is NC^-1

Discussion

735.	A few electric field lines for a system of two charges `Q_1` and `Q_2` fixed at two different points on the x-axis are shown in the figure. These lines suggest that A. `\|Q_(1)\| gt \|Q_(2)\|`B. `\|Q_(1)\| lt \|Q_(2)\|`C. at finite distnance to the left of `Q_(1)`, the electric field is zeroD. at a finitie distance to the right of `Q_(2)`, the electric field is zero
Answer» Correct Answer - A::D Number of field lines from `Q_(1)` is greater than that from `Q_(2)`. Therefore `\|Q_(1)\| gt \|Q_(2)\|`. Also, as right of `Q_(2)`, electric field would be zero.

Discussion

736.	A few electric field lines for a system of two charges `Q_1` and `Q_2` fixed at two different points on the x-axis are shown in the figure. These lines suggest that A. ` \|Q_1\| gt \|Q_2\|`B. ` \|Q_1\| gt \|Q_2\|`C. at a finite distance to the left of ` Q_1` the electric field is zerpD. at a finite distance to the left of ` Q_1` the electric field is zerp
Answer» Correct Answer - A::D The number of field lines is proprtional to the magnitude of the charge. Hence `\| Q_1 \| gt \| !_2 \|` .Field lines emerge from a positive charge and terminate on a negative charge . Hece `Q_1` is positve and `Q_2` is negative . Therefore , at any distance to the left of `Q_1` the electric field due to `Q_1` will be higher in magitude than that due to `Q_2` and cannot cancel each other. So the correct choices are `A` and `D` .

Discussion

737.	A cubical region of side a has its centre at the origin. It encloses three point charges , `-q` at `(0, -a//4 , 0),+3q at (0,0,0)` and `-q` at `(0,+a//4 ,0)`. Choose the correct option (s) (i) The net electric flux crossing the plane `x = +(q)/(2)` is equal to the net electric flux crossing the plane `x = -(a)/(2)` (ii) The net electric flux crossing the plane `y = +(a)/(2)` is more than the net electric flux crossing the plane `y = -(a)/(2)` (iii) The net electric flux crossing the entire region is `(q)/(epsilon_(0))` (iv) The net electric flux crossing the plane `z = +(a)/(2)` is equal to the net electric flux crossing the plane `x = +(a)/(2)`A. (a) The net electric flux crossing the plane `x=+a//2` is equal to the net electric flux crossing the plane `x=-a//2`B. (b) The net electric flux crossing the plane `y=+a//2` is more than the net electric flux crossing the plane `y=-a//2`.C. (c) The net electric flux crossing the entire region is `q/epsilon_0`D. (d) The net electric flux crossing the plane `z=+a//2` is equal to the net electric flux crossing the plane `x=+a//2`.
Answer» Correct Answer - A::C::D The electric flux passing through `x=+a/2`, `x=-a/2`, `z=+a/2` is same due to symmetry. The net electric flux through the cubical region is `(-q+3q-q)/(epsilon_0)=1/epsilon_0`.

Discussion

738.	Capacitance of a parallel plate capacitor can be increased by(a) increasing the distance between the plates (b) increasing the thickness of the plates (c) decreasing the thickness of the plates (d) decreasing the distance between the plates
Answer» (d) decreasing the distance between the plates

Discussion

739.	Two charges are placed in vacuum at a distance d apart. The force between them is F. If a medium of dielectric constant 2 is introduced between them, the force will now be(a) 4F (b) 2F (c) F/2 (d) F/4
Answer» Correct answer is (d) F/4

Discussion

740.	Which of the following statement(s) is/are correct?A. (a) If the electric field due to a point charge varies as `r^(-2.5)` instead of `r^-2`, then the Gauss law will still be valid.B. (b) The Gauss law can be used to calculate the field distribution around an electric dipole.C. (c) If the electric field between two point charges is zero somewhere, then the sign of the two charges is the same.D. (d) The work done by the external force in moving a unit positive charge from point A at potential `V_A` to point B at potential `V_B` is `(V_B-V_A)`.
Answer» Correct Answer - C::D (a) is not correct because it is valid only when `Epropr^-2` (b) is not correct (c) is correct as between two point charges we will get a point where the electric field due to the two point charges cancel out each other. (d) is correct when the work done is without accelerating the charge.

Discussion

741.	A few electric field lines for a system of two charges `Q_1` and `Q_2` fixed at two different points on the x-axis are shown in the figure. These lines suggest that A. (a) `\|Q_1\|gt\|Q_2\|`B. (b) `\|Q_1\|lt\|Q_2\|`C. (c) at a finite distance to the left of `Q_1` the electric field is zeroD. (d) at a finite distance to the right of `Q_2` the electric field is zero
Answer» Correct Answer - A::D The electric field lines are orginating from `Q_1` and terminating on `Q_2`. Therefore `Q_1` is positive and `Q_2` is negative. As the number of lines associated with `Q_1` is greater than that associated with `Q_2`, therefore `\|Q_1\|gt\|Q_2\|`. Option (a) is correct. At a finite distance on the left of `Q_1`, the electric field intensity cannot be zero because the electric field created by `Q_1` will be greater than `Q_2`. This is because the magnitude of `Q_1` is greater and the distance smaller `[EpropQ/r^2]` At a finite distance to the right of `Q_2`, the electric field is zero. Here, the electric field created by `Q_2` at a particular point will cancel out of the electric field created by `Q_1`.

Discussion

742.	Electron means ……
Answer» Electron means amber

Discussion

743.	The substances which acquire charges on rubbing are said to be …………
Answer» The substances which acquire charges on rubbing are said to be electrified

Discussion

744.	The charges in a electrostatics field are analogous to …… in a gravitational field.
Answer» The charges in a electrostatics field are analogous to mass in a gravitational field.

Discussion

745.	The branch of physics which deals with static electric charges or charges at rest is ……
Answer» The branch of physics which deals with static electric charges or charges at rest is electrostatics

Discussion

746.	The unit of permittivity is……
Answer» The unit of permittivity is C^-2N^-1m^-2

Discussion

747.	A charged particle is placed at the centre of two thin concentric spherical charged shells, made of non-conducting material. Figure A shows cross-section of the arrangement. Figure B gives the net flux `phi` through a Gaussian sphere centered on the particle, as a function of the radius r of the sphere. (a) Find charge on the central particle and shell A. (b) In which range of the finite values of r, is the electric field zero?
Answer» Correct Answer - (a). `17.7muC,-53.1muC` (b). No where

Discussion

748.	A thin conducting ring orf radius `R` is given a chareg `+Q`, Fig. The electric field at the centre `O` of the ring due to the charge on the part `AKB` of the ring is `E`. The electric field at the centre due to the charge on part `ACDB` of the ring is A. `3 E` along `KO`B. `E` along `OK`C. `E` along `KO`D. `3E` along `OK`
Answer» Correct Answer - B Charge on part `AKB = Q//4`, Fig `:. E` at O due to `AKB` is due to charge `Q//4`. In the part `ACDB`, intensity at `O` due to charges on `AC` and `DB` cancels out. Net intensity at `O` is due to charge `Q//4` on part `CD`. Its value must be `E` along OK.

Discussion

749.	An electron is moving round the nucleus of a hydrogen atom in a circular orbit of radius `r`. The coulomb force `vec(F)` between the two is (where `k=(1)/(4piepsilon_(0)))`A. `k(e^(2))/(r^(3))r`B. `-k(e^(2))/(r^(3))r`C. `k(e^(2))/(r^(2))r`D. `-k(e^(2))/(r^(3))hatr`
Answer» Correct Answer - B

Discussion

750.	If A is the area of each plate, charge on it is q and potential difference is V then the distance between the parallel plate capacitor isA. `(epsi_(0)AV)/(2q)`B. `(epsi_(0)AV)/(q)`C. `(2epsi_(0)AV)/(q)`D. `(AV)/(q)`
Answer» Correct Answer - B `V=E*d` `d=V/E=V/(sigma/epsi_(0))` `=(V/q)/(Aepsi_(0))=(VAepsi_(0))/q`

Discussion

Explore topic-wise InterviewSolutions in .

How does a torque affect the dipole in an electric field ?

Which rule gives you the direction of torque ?

At what points, dipole field intensity is parallel to the line joining the charges ?

Will an electric dipole have translational motion when placed in a non -uniform electric field? Give reason for your answer.

What happens when an electirc dipole is held in a non uniform electric field ?

When is the torque on a dipole in a field maximum ?

When does an electric dipole placed in a non-uniform electirc field experience a zero torque but non-zero force.

Why a small voltage can produce a reasonably large electric field?

Lines of force are imaginary; can they have any practical use?

The surface charge density of Earth is σ = -1.33 nC/m2. That is about 8.3 × 109 electrons per square metre. If that is the case why don’t we feel it?

Define point charge. Which law explains the interaction between charges at rest?

The force between two charges 0.06m apart is 5N. If each charge is moved towards the other by 0.04 m, then the force between them will becomeA. 7.20 NB. 11.25 NC. 22.50 ND. 45.00 N

A point charge q is rotating around a charge Q in a circle of radius r. The workdone on it by the coulomb force is(a) 2πrq (b) 2πQq (c) \(\frac {Q}{2ε^0r}\) (d) zero

The capacitor C of a spherical conductor of radius R is proportional to(a) R2(b) R(c) R-1(d) R0

The electric field due to a dipole at a distance r from its centre is proportional to(a)\(\frac {1}{r^\frac{3}{2}}\)(b)\(\frac {1}{r^3}\)(c)\(\frac {1}{r}\)(d) \(\frac {1}{r^3}\)

If n identical capacitors are connected in series and then in parallel then the ratio of effective capacity in parallel and in series combination i.e. `C_(P)/C_(S)` isA. nB. `1//n`C. `n^(2)`D. `1//n^(2)`

Two identical capacitors are first connected in series and then in parallel. The difference between their effective capacities is `3muF`. The capacity of each capacitor isA. `3muF`B. `4muE`C. `2muF`D. `5muE`

Define ‘Electric dipole'

The electric field lines never intersect. Justify.

What is mean by ‘Electric field lines’?

Electric field at a point is measued in terms of …………

The charge density in maximum at …………

At a large distance (r), the electric field due to a dipole varies as(a) \(\frac {1}{r}\)(b) \(\frac {1}{r^2}\)(c) \(\frac {1}{r^3}\) (d) \(\frac {1}{r^4}\)

The workdone in carrying a charge Q, once round a circle of radius R with a charge Q at the centre is-(a) \(\frac {Q_1Q_2}{4πε_0 R^2}\)(b) Zero(c) \(\frac {Q_1Q_2}{4πε_0 R}\)(d) infinite

Capacitor is a device to store …………

The process of isolating a certain region of space from external field is called ………

Two plates are 1 cm apart and the potential difference between them is 10 V. The electric field between the plates is (a) 10 NC-1 (b) 250 NC-1(c) 500 NC-1(d) 1000 NC-1

The space around the test charge, in which it experiences a force is known as field …………

Two plates are 2 cm apart. If a potential difference of 10 V is applied between them. The electric field between the plates will be(a) 20 NC-1 (b) 500 NC-1 (c) 5 NC-1 (d) 250 NC-1

The unit of electric field in tensity is …………

Capacitance of a parallel plate capacitor can be increased by(a) increasing the distance between the plates (b) increasing the thickness of the plates (c) decreasing the thickness of the plates (d) decreasing the distance between the plates

Two charges are placed in vacuum at a distance d apart. The force between them is F. If a medium of dielectric constant 2 is introduced between them, the force will now be(a) 4F (b) 2F (c) F/2 (d) F/4

Electron means ……

The substances which acquire charges on rubbing are said to be …………

The charges in a electrostatics field are analogous to …… in a gravitational field.

The branch of physics which deals with static electric charges or charges at rest is ……

The unit of permittivity is……

An electron is moving round the nucleus of a hydrogen atom in a circular orbit of radius `r`. The coulomb force `vec(F)` between the two is (where `k=(1)/(4piepsilon_(0)))`A. `k(e^(2))/(r^(3))r`B. `-k(e^(2))/(r^(3))r`C. `k(e^(2))/(r^(2))r`D. `-k(e^(2))/(r^(3))hatr`

If A is the area of each plate, charge on it is q and potential difference is V then the distance between the parallel plate capacitor isA. `(epsi_(0)AV)/(2q)`B. `(epsi_(0)AV)/(q)`C. `(2epsi_(0)AV)/(q)`D. `(AV)/(q)`