Electric Field and Potential Questions and Answers

4x 4x b ES0045 7 At any point on the perpendicular bisector of the line joining two equal and opposite charges 1 the electric field is zero 2 the electric potential is zero 3 the electric potential decreases with increasing distance from their mid point 4 the electric field is perpendicular to the line joining the charges 52 53

52 Pre Medical Physics 56 Four charges Q Q Q and Q are situated at the corners of a square in a sequence then at the centre of the square 1 E 0 V 0 3 E0 V 0 2 E 0 V 0 4 E 0 V 0

English A charged parallel plate capacitor is kept in a magnetic field that is perpendicular to the plates Figure The distance between the plates is d The magnetic field is B Inside the capacitor near the negatively charged plate is a source of slow electrons which is emitting electrons in different directions with same speed v Assume that vertically below the source there is origin on the other plate Neglect gravity Mass of electron m Charge on electron q Electric field E B Options 1 The electrons form a circular patch on the positively charged plate 2mv 2 The radius of circular patch can be qB my 3 The radius of circular patch can be qB 4 The radius of circular patch can be approx 2mdy2 li d Please solve all the Options

circumference of a circle of radius R as shown in the figure What is electrostatic force on do placed at the centre of the circle 9 1 3 990 2 2R 0 2990 4TEOR 9 Add your responses Type Text 90 q 2 4 q 8990 ATER Asked by 2285483 aesl id Standard XII Stream NEET Jul 14 2021 5 46 qqo 2 250R Type your answer here OR you can upload an lattachment from the option below

ES0053 55 The potential at a distance R 2 from the centre of a conducting sphere of radius R containing charge Q will be 1 0 3 Q 4x R 2 8 R Q 4 2x R ES0054

3 4neo QX 4 zero ES0047 Certain positive charge is given to a conductor Then its potential 1 is maximum at the surface 2 is maximum at the centre 3 remains same throughout the conductor 4 is maximum somewhere between the surface and the centre ES0048

28 An electron in an electron microscope with initial velocity vi enters a region of a stray transverse electric field E The time taken for the change in its de Broglie wavelength from the initial value of to 1 3 is proportional to a E c 1 JE E d E

The electric field in a region is given as E 2xy i 2x y y where all quantities are in S I units If the electric potential at 1 m 1 m is 5 V then the electric potential at 2 m 1 m is y a i faya E G AH Af S 1 a A B 2xy i i 2x y y j 25 C 2 V Correct Answer 17 3 V 14 3 V 1 m 1 m 5 a 2 m 1 m

3 An electric field is expressed as E 21 3 Find the potential difference VA VB between two points A and B whose position vectors are given by r 1 2 and r 21 1 3k A 1 1 V 2 1V 3 2 V 4 3 V

A conducting sphere of radius R and a concentric thick spherical shell of inner radius 2R and outer radius 3R is shown in figure A cha 10Q is given to the shell and inner sphere is earthed Then charge on inner sphere is O 4Q O 100 O zero O none

Q 27 Three charges 2q q and q lie at vertices of a triangle The value of electric field and electric potential at the centroid of triangle will be E and V both are nonzero E and V both are zero E is nonzero but V is zero E is zero and V is nonzero a b c d

Use the following constants if necessary Coulomb constant k 8 987 10 Nm C Vacuum permitivity 0 8 854 x 10 F m Magnetic Permeability of vacuum M40 12 566370614356 x 10 7 H m Magnitude of the Charge of one electron e 1 60217662 x 10 19 C Mass of one electron me 9 10938356 x 10 1 kg Unless specified otherwise each symbol carries their usual meaning For example C means micro coulomb dq x A uniform ring charge of radius a 6 m and total charge Q 18 Cas shown in Figure The field E at point P at a distance 8 m on the axis due to the charge Qis Magtitude of the Electric field Give your answer up to at least three significance digits

33 A point charge q is kept at A The potential at point P at distance r from it is v and twice of this charge is distributed uniformly on the surface of a hollow sphere of radius 4r with centre at point A the total potential at point P is 3v 0 2 NATO 3 v 4

For the same question asked earlier different expert has given different answers Confusion is between option 1 3 Package says 3rd Please explain A thin diamagnetic rod is placed vertically between the poles of an electromagnet When the current in the electromagnet is switched on then the diamagnetic rod is pushed up out of the horizontal magnetic field Hence the rod gains gravitational potential energy The work required to do this comes from NEET 2018 1 The current source 2 The magnetic field 3 The induced electric field due to the changing magnetic field 4 The lattice structure of the material of the rod

The rod of non uniform linear charge density ax where a 3 00 nC m placed on the x axis such a way that one of its ends is at the origin and the other end is at 0 4 m Find the electric potential on the y axis at 0 m 0 3 m a 0 984 V b 1 37 V c 6 72 V d 2 31 V

Figure shows three electric field lines If FA FB and Fe are the forces on a test charge q at the positions A B and C respectively then a FA FB Fc C FA FB FC B b FA FB Fc d FA FB FC

In a certain region of space the electrostatic field depends only on the coordinates x and y as follows E 0 for x y ro 2 E a xi y x y for x y ro where a is a positive constant and i and are the unit vec tors along the X and Y axes Find the charge within a sphere of radius 2r with the centre at the origin

The two equal and opposite charges with magnitude 1 7 C and the third charge 2 8 C is placed as shown in the figure Determine the electric potential energy of the system of charges a 0 043 J b 0 00043 J c 2 1 J d 42 J y 4 0 cm 2 8 C 1 7 C 1 7 C x 6 0 cm

Question 2 25 points Two charges q 4 C and q 4 C are located as shown in the Figure In the Figure d 0 2 m and s 0 4 m a Find the x y componenets of the electric field due to charges E due to charge q and E due to q2 at at point P b Find E due to charge q and E due to q2 at at point P c Write E and E in vector form d Find the total electric field E at point P and write E in vector form 99 TO TO d 2 S S P

11 A circular current loop of radius 3 0 cm carries a current of 1 5 mA a What is the magnitude of ts magnetic dipole moment b If the dipole is oriented at 30 degrees to a uniform magnetic field of magnitude 0 50 T what is the magnitude of the torque it experiences

Calculate the Electric Field at P Show calculation of the vector components net x and y components and resultant magnitude and direction Calculate the Electric Potential at P from Figure 1 Assume a potential of zero at infinity Calculate the Electric Potential Energy of assembling the charges in Figure 1 Assume a potential of zero when the charges are infinitely far apart from each other 4 m 2 m A q 0m O P 3m O 9 6 m q 1 0 C at x 0m q 3 0 C at x 3 0 my 4 0 m q 2 0 C at x 6 0 m P at x 3 0 m on the x axis

A system of two charges QA 2 5 10 7 and QB 2 5 10 7C are located at points A 0 0 15 cm and B 0 0 15 cm respectively The electric dipole moment of system is O O O C 2 5 107 Cm 5 107 Cm 7 5 10 Cm zero

A point charge Q 4 10 7 C is placed at a point in free space How much work is required to bring a charge 2 nC from infinity to a point 9 cm from charge Q O 3 104J 08x10 5 J 2x10 5 J 5 10 5 J

ALLEN Build Up Your Understanding Two point charges placed at a distance Y in air exert a force F The distance at which they exert same force when placed in a certain medium dielectric constant K is 1 K 3 r K 2 r K 4 K

Interactive LeamingWare 18 1 offers some perspective on this problem Two tiny spheres have the same mass and carry charges of the same magnitude The mass of each sphere 2 06 10 kg The gravitational force that each sphere exerts on the other is balanced by the electric force Determine the charge magnitude Number Turits

13 The separation between two protons so that the electrostatic repulsive force acting on either of them is equal to its weight is Given charge of proton 1 67 x 107 kg and g 9 8 ms 2 A 0 119 m B 0 25 m 1 6 10 C mass of proton C 0 30 m D 0 35 m

20 Two point charges 4 C and 10 C are placed 10 cm apart in air A dielectric slab of large length and bread and thickness 5 cm is placed between the charges When the force of attraction between the charges if the dielectric constant of the medium is 9 is A 9 N B 11 N C 5 N D 12 N ASC Study Centre Vijay

15 A charge q is divided into two parts and the two parts are kept apart in air The force between them is maximu if the two parts have the charge A each B each 4 9 C and 39 4 4 2913 D and

17 Two electric bulbs A and B rated 200 V 100 W and 200 V 60 W are connected in series to a 200 V line Then the potential drop across 1 Each bulb is 200 V 3 100W bulb is smaller than that across 60 W bulb 4 Each bulb is 100 V 2 100 W bulb is greater than that across 60 W bulb

14 Electric charges 1 C 1 C and 2 C are placed in air at corners A B and C respectively of an equilateral tri ABC of side 10 cm The resultant force on the charge at C is A 0 9 N B 1 8 N C 2 7 N D 3 6 N

19 A cylinder has a radius of 2 1 cm and a length of 8 8 cm Total charge 6 1 x 107 C is distributed uniformly throughout The volume charge density is A 5 3 x 10 C m 3 B 5 3 x 10 Cm C 8 5 x 10 C m D 5 0 x 10 Cm

An electric dipole is placed making at an angle 60 with an electric field of strength 4 x 105 N C It experiences a torque equal to 8 3 N m Calculate the charge on the dipole if it is of length 4 cm Question Type Single Correct Type 1 10 4 C 2 10 C 3 10 2 C

A composite spherical shell of radius r 10 cm and wall thickness t 0 1 mm is made of copper except an equatorial strip of width b 0 2 cm which is made of aluminium When the poles of the sphere are connected across an ideal battery of terminal voltage V 0 1 mV a current I 5 12 A flows through it If the aluminium strip is replaced by an iron strip of identical dimensions and the experiment is repeated with the same battery what current will flow through the battery Resistivities of aluminium and iron are pA 0 03 22 mm m and pre 0 10 22 mm m

69 Charges Q and 20 are given to parallel plates A and B respectively and they are separated by a small distance The capacitance of the given arrangement Qo 200 is C Now plates A and B are connected to positive and negative terminals of battery of potential difference V 200 C respectively as shown then the work done by the battery is 3 2007 C 50 2 4 40 C 60 C A B V 200 C

21 Two pith balls each of mass 30 mg are suspended by two threads from a support When charged identically the two pith balls move apart by 0 08 m the threads making angle 60 with each other The charge on each pith ball is B 11 9 nC C 4 9 nC D None A 10 9 nC 2 A positive point charge which is free to move is placed inside a hollow conducting sphere with negative charge away from its centre It will A move towards the centre B remain stationary C move towards the nearer wall of the conductor D oscillate between the centre and the nearer wall

In the given figure a diode D is connected to an external resistance R 10022 and an e m f of 3 5V If the barrier potential developed across the diode is 0 5 V the curren in the circuit will be A 35 mA B 30 mA F 3 5V 10002 www R C 40 mA D 20 mA

3 In a uniformly charged sphere of total charge Q and radius R the electric field E is plotted as function of distance from the centre which would graph correspond to the above will be a c E E Rr Rr b d E E t Rr Rr

A thin spherical shell is given a char ge q 4uc uniformly distributed over surface Consider abpoint P outside s hell at distance of 2m from surface I f the tmradius of shell is 1m whatvis the electric field at point P Answer is given as 9 KNC whereas m y answer is 4 KNC

The electric potential at a point in free space due to a charge Q coulomb is Q x 1011 volts The electric field at that point is AIPMT Prelims 2008 1 12 Q x 1022 volt m 2 4 TE Q x 1022 volt m 3 12 Q x 1020 volt m 4 4 TE Q 1020 volt m

Plz explain both the questions both are on same concept 3 An charged insulated spherical conductor A is brought near another grounded conductor B then CST CSS 02 P 4 1 Charge and potential of B both remains constant 2 Both charge and potential of B changes 3 Charge on B remains constant but potential changes 4 Charge on B changes but potential remains constant An uncharged insulated non metallic solid sphere A is brought near a positively charged insulated metallic hollow sphere B then neglect polarization Charge and potential of B both remains constant 2 Both charge and potential of B changes 3 Charge on B remains constant but potential increases 4 Charge on B remains constant but potential dooro000

Oscillating magnetic field in a plane electromagnetic wave is given by B 4 x 10 sin 9 x 10 t 30x tesla Expression for oscillating electric field in N C 1 will be 600 sin 9x 10 t 30x k 600 sin 9x10 t 30x k X E 1200 sin 9 x 10 t 30x k 1200sin 9x10 t 30x k

Consider two charges q and q placed at B and C of an equilateral triangle ABC For this system the total charge is zero But the electric field intensity at Awhich is equidistant from B and C is not zero Why

In the figure shown A and B are two points at a distance d from each of two equal and unlike chartes The work done in transferring a negative charge q from Ato B is A io 1 zero B 2 478

1 A point charge Q is kept at a distance 3a from the centre of a spherical conducting shell of charge 3Q and radius a Assuming K 4TEO statement s Before closing switch the potential of the shell is Q0 3a Before closing switch the electric field at C due to the spherical shell is 8KQ 3a 3Q KQ 9a K y Ex mark the co

Q2 20 marks A conducting spherical shell Figure 1 having inner radius a 1 8 m and outer radius b 2 4 m carries a charge of Q 4 0 nC There is a charge of Q2 2 0 nC at the center of the sphere Find the electric field at a r 1 5 m b r 2 0 m and c r 2 5 m Draw electric field line in each case d What is the distribution of charge on the spherical shell b Q a Figure 1

27 180 Same current is flowing in three infinitely long thin wire along positive x y and z direction The magnetic field at a point 0 0 a would be 2 a Ho i i H

particle of mass m and charge q is thrown perpendicular to an electric field of tensity E with an initial velocity v The particle moves a distance x perpendicular to the field and a distance y along the direction of the field If y ax then the ais given by

t ht ed d 3 2 4TE MR 4TE R 23 Select from the four particles that contribute to the electric field at point P on the surface 93 1 93 and 94 3 91 92 93 and 94 4 94 P 2 9 92 94 4 9 and 9 91

23 Select from the four particles that contribute to the electric field at point P on the surface 9 1 93 and 94 3 9 92 93 and 94 02 94 P 2 91 92 94 4 9 and 92

A particle of charge q and mass m is released at a distance x from axis of ring having charge Q and radius R For x R the time period of oscillation of charged particle is 1 2T 2 3 2 3 4 mR Qq Qq mp3 D3 2 4 4 E MR Qq Qq 4 E R