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question_answer1)
Two balls of same mass and carrying equal charge are hung from a fixed support of length l. At electrostatic equilibrium, assuming that angles made by each thread is small, the separation, x between the balls is proportional to:
A)
l done
clear
B)
\[{{l}^{2}}\] done
clear
C)
\[{{l}^{2/3}}\] done
clear
D)
\[{{l}^{1/3}}\] done
clear
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question_answer2)
The force of repulsion between two electrons at a certain distance is F. The force between two protons separated by the same distance is \[({{m}_{p}}=1836{{m}_{e}})\]
A)
2F done
clear
B)
F done
clear
C)
1836F done
clear
D)
\[\frac{F}{1836}\] done
clear
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question_answer3)
The force between two small charged spheres having charges of \[1\times {{10}^{-7}}C\] and \[2\times {{10}^{-7}}C\]
A)
\[4.5\times {{10}^{-}}^{2}N\] done
clear
B)
\[4.5\times {{10}^{-}}^{3}N\] done
clear
C)
\[5.4\times {{10}^{-2}}N\] done
clear
D)
\[5.4\times {{10}^{-3}}N\] done
clear
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question_answer4)
Two charge q and -3q are placed fixed on x-axis separated by distance d. Where should experience any force?
A)
\[\frac{d-\sqrt{2}d}{2}\] done
clear
B)
\[\frac{d+\sqrt{3}d}{2}\] done
clear
C)
\[\frac{d+3d}{2}\] done
clear
D)
\[\frac{d-\sqrt{5}d}{2}\] done
clear
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question_answer5)
Two insulated charged metallic sphere P and Q have their centers separated by distance of 60 cm. The radii of P and Q are negligible
A)
\[5.2\times {{10}^{-4}}N\] done
clear
B)
c \[2.5\times {{10}^{-3}}N\] done
clear
C)
\[1.5\times {{10}^{-3}}N\] done
clear
D)
\[3.5\times {{10}^{-4}}N\] done
clear
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question_answer6)
If a charge q is placed at the center of the line joining two equal charges Q such that the system is in equilibrium then the value of q is
A)
Q/2 done
clear
B)
-Q/2 done
clear
C)
Q/4 done
clear
D)
-Q/4 done
clear
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question_answer7)
Two positive ions, each carrying a charge q, are separated by a distance d. If F is the force of repulsion between the ions, the number of electrons missing from each ion will be (e being the charge of an electron)
A)
\[\frac{4\pi {{\varepsilon }_{0}}F{{d}^{2}}}{{{e}^{2}}}\] done
clear
B)
\[\sqrt{\frac{4\pi {{\varepsilon }_{0}}F{{e}^{2}}}{{{d}^{2}}}}\] done
clear
C)
\[\sqrt{\frac{4\pi {{\varepsilon }_{0}}F{{d}^{2}}}{{{e}^{2}}}}\] done
clear
D)
\[\frac{4\pi {{\varepsilon }_{0}}F{{d}^{2}}}{{{q}^{2}}}\] done
clear
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question_answer8)
A solid conducting sphere of radius a has a net positive charge 2Q. A concluding spherical shell of inner radius b and outer radius c is concentric with the solid sphere and has a net charge-Q. The surface charge density on the inner and outer surfaces charge density on the inner and outer surfaces of the spherical shell will be
A)
\[-\frac{2Q}{4\pi {{b}^{2}}},\frac{Q}{4\pi {{c}^{2}}}\] done
clear
B)
\[-\frac{Q}{4\pi {{b}^{2}}},\frac{Q}{4\pi {{c}^{2}}}\] done
clear
C)
\[0,\frac{Q}{4\pi {{c}^{2}}}\] done
clear
D)
None of the above done
clear
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question_answer9)
Three charges +q, +2q and +4q are connected by string as shown in the figure. What is ration of tension in the strings AB and BC?
A)
1 : 2 done
clear
B)
1 : 3 done
clear
C)
2 : 1 done
clear
D)
3 : 1 done
clear
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question_answer10)
1 C charge is equivalent to charge on how much number of protons?
A)
\[6\times {{10}^{18}}\] done
clear
B)
\[7\times {{10}^{19}}\] done
clear
C)
\[8\times {{10}^{20}}\] done
clear
D)
\[9\times {{10}^{21}}\] done
clear
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question_answer11)
The figure shows a charge +q at point P held in equilibrium in air with the help of four +q charges situated at the vertices of a square. The net electrostatic force on q is given by
A)
Newton's done
clear
B)
Coulomb's law done
clear
C)
Principle of superposition done
clear
D)
Net electric flux out the position of +q. done
clear
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question_answer12)
The metal knob of a gold leaf electroscope is touched with a positively charged rod. When it is taken away the leaves stay separated. Now the metal knob is touched by negatively charged rod. The separation between the leaves
A)
increases done
clear
B)
decreases done
clear
C)
remains same done
clear
D)
first increases then decreases. done
clear
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question_answer13)
Which of the following fraphs shows the correct variation of force when the distance r between two charges varies?
A)
B)
C)
D)
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question_answer14)
The electric charge required to expand a soap bubble to twice its dimension is
A)
\[8\pi \sqrt{{{\in }_{0}}\,{{r}^{3}}(7\Pr +12T)}\] done
clear
B)
\[8\pi \sqrt{{{\in }_{0}}{{r}^{2}}(7\Pr +12T)}\] done
clear
C)
\[8\pi \sqrt{{{\in }_{0}}{{r}^{3}}(6\Pr +12T)}\] done
clear
D)
\[\ell \] done
clear
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question_answer15)
A large no conducting sheet M is given a uniform charge density. Two uncharged small metal rods A and B are placed near the sheet as shown in figure. Then
A)
M attracts A done
clear
B)
M attracts B done
clear
C)
A attracts B done
clear
D)
All of these done
clear
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question_answer16)
Three charges \[{{q}_{1}},\text{ }+{{q}_{2}}\] and \[{{q}_{3}}\]are place as shown in the figure. The x-component of the force on\[-{{q}_{1}}\]is proportional to
A)
\[\frac{{{q}_{2}}}{{{b}^{2}}}-\frac{{{q}_{3}}}{{{a}^{2}}}\cos \theta \] done
clear
B)
\[\frac{{{q}_{2}}}{{{b}^{2}}}+\frac{{{q}_{3}}}{{{a}^{2}}}\sin \theta \] done
clear
C)
\[\frac{{{q}_{2}}}{{{b}^{2}}}+\frac{{{q}_{3}}}{{{a}^{2}}}\cos \theta \] done
clear
D)
\[\frac{{{q}_{2}}}{{{b}^{2}}}-\frac{{{q}_{3}}}{{{a}^{2}}}\sin \theta \] done
clear
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question_answer17)
A charged ball B hangs from a silk thread S, which makes an angle \[\theta \] with a large charged conducting sheet P, as shown in the figure. The surface charge density \[\sigma \] of the sheet is proportional to
A)
\[\cot \theta \] done
clear
B)
\[\cos \theta \] done
clear
C)
\[\tan \theta \] done
clear
D)
\[\sin \theta \] done
clear
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question_answer18)
ggTwo particles A and B having equal charges are placed at a distance d apart. A third charged particle placed on the perpendicular bisection of AB at distance x. The third particle experiences maximum force when
A)
\[x=\frac{d}{\sqrt{2}}\] done
clear
B)
\[x=\frac{d}{2}\] done
clear
C)
\[x=\frac{d}{2\sqrt{2}}\] done
clear
D)
\[x=\frac{d}{3\sqrt{2}}\] done
clear
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question_answer19)
Among two discs A and B, first have radius 10 cn and charge \[{{10}^{-6}}\mu C\]and second have radius 30 cm and charge \[{{10}^{-5}}C.\] When they are touched, charge on both \[{{q}_{A}}\]and \[{{q}_{B}}\]respectively will, be
A)
\[{{q}_{A}}=2.75\mu C,{{q}_{B}}=3.15\mu C\] done
clear
B)
\[{{q}_{A}}=1.09\mu C,{{q}_{B}}=5.5\mu C\] done
clear
C)
\[{{q}_{A}}={{q}_{B}}=5.5\mu C\] done
clear
D)
None of these done
clear
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question_answer20)
Two pith balls carrying equal charges are suspended from a common point by strings of equal the balls now become
A)
\[\left( \frac{r}{\sqrt[3]{2}} \right)\] done
clear
B)
\[\left( \frac{2r}{\sqrt{3}} \right)\] done
clear
C)
\[\left( \frac{2r}{3} \right)\] done
clear
D)
\[{{\left( \frac{r}{\sqrt{2}} \right)}^{2}}\] done
clear
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question_answer21)
Two equal point charges each of \[3\mu C\] are separated by a certain distance in meters. If they are located at \[(\hat{i}+\hat{j}+\hat{k})\] and \[(2\hat{i}+3\hat{j}+\hat{k})\], then the electrostatic force between them is
A)
\[9\times {{10}^{3}}N\] done
clear
B)
\[16\times {{10}^{-3}}N\] done
clear
C)
\[{{10}^{-3}}N\] done
clear
D)
\[9\times {{10}^{-2}}N\] done
clear
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question_answer22)
In fig., two equal positive point charges \[{{q}_{1}}={{q}_{2}}=2.0\mu C\] interact with a third point charge \[Q=4.0\mu C\]. The magnitude, as well as direction, of the net force on Q is
A)
0.23 N in the +x-direction done
clear
B)
0.46 N in the +x-direction done
clear
C)
0.23 N in the +x-direction done
clear
D)
0.46 N in the +x-direction done
clear
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question_answer23)
Force between two identical charges placed at a distance of r in vacuum is F, Now a slab of dielectric of dielectric contrant 4 is inserted between these two charges. If the thickness of the slab is r/2, then the force between the charges will become
A)
F done
clear
B)
\[\frac{3}{5}F\] done
clear
C)
\[\frac{4}{9}F\] done
clear
D)
\[\frac{F}{2}\] done
clear
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question_answer24)
A total charge Q is broken in two parts \[{{Q}_{1}}\] and \[{{Q}_{2}}\] and they are placed at a distance R from each
A)
\[{{Q}_{2}}=\frac{Q}{R},{{Q}_{1}}=Q-\frac{Q}{R}\] done
clear
B)
\[{{Q}_{2}}=\frac{Q}{4},{{Q}_{1}}=Q-\frac{2Q}{3}\] done
clear
C)
\[{{Q}_{2}}=\frac{Q}{4},{{Q}_{1}}=\frac{3Q}{4}\] done
clear
D)
\[{{Q}_{1}}=\frac{Q}{2},{{Q}_{2}}=\frac{Q}{2}\] done
clear
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question_answer25)
Two particle of equal mass m and charge q are placed at a distance of 16 cm. They do not experience any force. The value of \[\frac{q}{m}\] is
A)
1 done
clear
B)
\[\sqrt{\frac{\pi {{\varepsilon }_{0}}}{G}}\] done
clear
C)
\[\sqrt{\frac{G}{4\pi {{\varepsilon }_{0}}}}\] done
clear
D)
\[\sqrt{4\pi {{\varepsilon }_{0}}}\] done
clear
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question_answer26)
A uniformly charged conducting sphere of 4.4 m diameter has a surface charge density of \[60\mu C{{m}^{-2}}.\]The charge on the sphere is
A)
\[7.3\times {{10}^{-3}}C\] done
clear
B)
\[3.7\times {{10}^{-6}}C\] done
clear
C)
\[7.3\times {{10}^{-6}}C\] done
clear
D)
\[3.7\times {{10}^{-3}}C\] done
clear
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question_answer27)
Three identical spheres, each having a charge q And radius R, are kept in such a way that each touches the other two. The magnitude of the electric force any sphere due to the other two is
A)
\[\frac{1}{4\pi {{\varepsilon }_{0}}}{{\left( \frac{q}{R} \right)}^{2}}\] done
clear
B)
\[\frac{\sqrt{3}}{4\pi {{\varepsilon }_{0}}}{{\left( \frac{q}{R} \right)}^{2}}\] done
clear
C)
\[\frac{\sqrt{3}}{16\pi {{\varepsilon }_{0}}}{{\left( \frac{q}{R} \right)}^{2}}\] done
clear
D)
\[\frac{\sqrt{5}}{16\pi {{\varepsilon }_{0}}}{{\left( \frac{q}{R} \right)}^{2}}\] done
clear
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question_answer28)
Two identical blocks are kept on a frictionless horizontal table connected by a spring of stiffness k and of original length \[{{l}_{0}}.\] A total charge Q is distributed of spring at equilibrium of equal to x. Value of Q is
A)
\[2{{\ell }_{0}}\sqrt{4\pi {{\varepsilon }_{0}}k\left( {{\ell }_{0}}+x \right)}\] done
clear
B)
\[2x\sqrt{4\pi {{\varepsilon }_{0}}k\left( {{\ell }_{0}}+x \right)}\] done
clear
C)
\[2\left( {{\ell }_{0}}+x \right)\sqrt{4\pi {{\varepsilon }_{0}}kx}\] done
clear
D)
\[\left( {{\ell }_{0}}+x \right)\sqrt{4\pi {{\varepsilon }_{0}}kx}\] done
clear
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question_answer29)
Two small balls having the same mass and charge and located on the same vertical at heights \[{{h}_{1}}\] and \[{{h}_{2}}\] are thrown in the same direction along the horizontal at the same velocity v. The first ball touches the ground at a distance \[\ell \] from the initial vertical. At what height \[{{H}_{2}}\]will the second ball be at this instant? The air drag and the effect of the charges induced on the ground should be neglected.
A)
\[{{h}_{1}}+{{h}_{2}}-g{{\left( \frac{\ell }{v} \right)}^{2}}\] done
clear
B)
\[{{h}_{1}}-{{h}_{2}}-g{{\left( \frac{\ell }{v} \right)}^{2}}\] done
clear
C)
\[{{h}_{1}}+{{h}_{2}}-g{{\left( \frac{\ell }{v} \right)}^{1/2}}\] done
clear
D)
\[\frac{{{h}_{1}}+{{h}_{2}}}{2}-g{{\left( \frac{\ell }{v} \right)}^{2}}\] done
clear
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question_answer30)
Two identical beads each have a mass m and charge q. When placed in a hemispherical bowl of radius R with frictionless, nonconductive walls, the beads move, and at equilibrium the distance between them is R (Fig.). Determine the charge on each bead.
A)
\[R{{\left( \frac{mg}{{{k}_{e}}\sqrt{3}} \right)}^{1/2}}\] done
clear
B)
\[R{{\left( \frac{mg}{{{k}_{e}}\sqrt{2}} \right)}^{1/2}}\] done
clear
C)
\[R{{\left( \frac{mg}{{{k}_{e}}2\sqrt{3}} \right)}^{1/2}}\] done
clear
D)
\[R{{\left( \frac{2\,mg}{{{k}_{e}}\sqrt{3}} \right)}^{1/2}}\] done
clear
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question_answer31)
If \[{{E}_{q}}\] be the electric field strength of a short dipole at a point on its axial line and \[{{E}_{e}}\]that on the equatorial line at the same distance, the n
A)
\[{{E}_{e}}=2{{E}_{a}}\] done
clear
B)
\[{{E}_{a}}=2{{E}_{e}}\] done
clear
C)
\[{{E}_{a}}={{E}_{e}}\] done
clear
D)
None of these done
clear
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question_answer32)
When an electric dipole \[\vec{P}\] is placed in a uniform electric field E then at what angle between P and \[\vec{E}\] the value of torque will be maximum?
A)
\[90{}^\circ \] done
clear
B)
\[0{}^\circ \] done
clear
C)
\[180{}^\circ \] done
clear
D)
\[45{}^\circ \] done
clear
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question_answer33)
Which of the following graphs shows the correct variation in magnitude of torque on an electric dipole rotated in a uniform electric field from stable equilibrium to unstable equilibrium?
A)
B)
C)
D)
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question_answer34)
A rod of length 2.4 m and radius 4.6 mm carries a negative charge of \[4.2\times {{10}^{-7}}C\] spread uniformly over it surface. The electric field near the mid-point of the rod, at a point on its surface is
A)
\[-\,8.6\times {{10}^{5}}N{{C}^{-1}}\] done
clear
B)
\[8.6\times {{10}^{4}}N{{C}^{-1}}\] done
clear
C)
\[-\,6.7\times {{10}^{5}}N{{C}^{-1}}\] done
clear
D)
\[6.7\times {{10}^{4}}N{{C}^{-1}}\] done
clear
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question_answer35)
If electric field in a region is radially outward with magnitude \[E=Ar\], the charge contained in a sphere of radius r centered at the origin is
A)
\[\frac{1}{4\pi {{\varepsilon }_{0}}}A{{r}^{3}}\] done
clear
B)
\[A{{r}^{3}}4\pi {{\varepsilon }_{0}}\] done
clear
C)
\[\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{A}{{{r}^{3}}}\] done
clear
D)
\[\frac{4\pi {{\varepsilon }_{0}}A}{{{r}^{3}}}\] done
clear
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question_answer36)
The electric field intensity just sufficient to balance the earth?s gravitational attraction on an electron will be: (given mass and charge of an electron respectively are \[9.1\times {{10}^{-31}}kg\]and \[1.6\times {{10}^{-19}}C.\])
A)
\[-\,5.6\times {{10}^{-11}}N/C\] done
clear
B)
\[-\,4.8\times {{10}^{-15}}N/C\] done
clear
C)
\[-\,1.6\times {{10}^{-19}}N/C\] done
clear
D)
\[-\,3.2\times {{10}^{-19}}N/C\] done
clear
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question_answer37)
The insulation property of air breaks down when the electric field is \[3\times {{10}^{6}}V{{m}^{-1}}.\] The maximum charge that can be given to a sphere of diameter 5 m is approximately
A)
\[2\times {{10}^{-2}}C\] done
clear
B)
\[2\times {{10}^{-3}}C\] done
clear
C)
\[2\times {{10}^{-4}}C\] done
clear
D)
\[2\times {{10}^{-5}}C\] done
clear
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question_answer38)
A hollow insulated conduction sphere is given a positive charge of \[10\mu C.\] What will be the electric field at the center of the sphere if its radius is 2m?
A)
Zero done
clear
B)
\[5\mu C{{m}^{-2}}\] done
clear
C)
\[20\mu C{{m}^{-2}}\] done
clear
D)
\[8\mu C{{m}^{-2}}\] done
clear
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question_answer39)
The number of electric lines of force that radiate outwards from one coulomb of charge in vacuum is
A)
\[1.13\times {{10}^{11}}\] done
clear
B)
\[1.13\times {{10}^{10}}\] done
clear
C)
\[0.61\times {{10}^{11}}\] done
clear
D)
\[0.61\times {{10}^{9}}\] done
clear
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question_answer40)
The electric intensity due to a dipole of length 10 cm and having a charge of \[500\mu C\], at a point on the axis at a distance 20 cm from one of the charges in air, is
A)
\[6.25\times {{10}^{7}}N/C\] done
clear
B)
\[9.28\times {{10}^{7}}N/C\] done
clear
C)
\[13.1\times {{10}^{11}}N/C\] done
clear
D)
\[20.5\times {{10}^{7}}N/C\] done
clear
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question_answer41)
ABC is an equilateral triangle. Charges +q are placed at each corner as shown in fig. The electric intensity at center O will be
A)
\[\frac{1}{4\pi {{\in }_{0}}}\frac{q}{r}\] done
clear
B)
\[\frac{1}{4\pi {{\in }_{0}}}\frac{q}{{{r}^{2}}}\] done
clear
C)
\[\frac{1}{4\pi {{\in }_{0}}}\frac{3q}{{{r}^{2}}}\] done
clear
D)
Zero done
clear
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question_answer42)
Intensity of an electric field (E) depends on distance r, due to a dipole, is related as
A)
\[E\propto \frac{1}{r}\] done
clear
B)
\[E\propto \frac{1}{{{r}^{2}}}\] done
clear
C)
\[E\propto \frac{1}{{{r}^{3}}}\] done
clear
D)
\[E\propto \frac{1}{{{r}^{4}}}\] done
clear
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question_answer43)
If the dipole of moment \[2.57\times {{10}^{-17}}cm\] is placed into an electric field of magnitude \[3.0\times {{10}^{4}}N/C\]such that the fields lines are aligned at \[30{}^\circ \] with the line joining P to the dipole, what torque acts on the dipole?
A)
\[7.7\times {{10}^{-13}}Nm\] done
clear
B)
\[3.855\times {{10}^{-13}}Nm\] done
clear
C)
\[3.855\times {{10}^{-15}}Nm\] done
clear
D)
\[7.7\times {{10}^{-15}}Nm\] done
clear
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question_answer44)
An electric dipole is placed at an angle of \[30{}^\circ \]with an electric field of intensity \[2\times {{10}^{5}}N{{C}^{-1}}\], it experiences a torque of 4 Nm. Calculate the charge on the dipole if the dipole length is 2 cm.
A)
\[8mC~~~~\] done
clear
B)
\[\,4mC\] done
clear
C)
\[8\mu C\] done
clear
D)
\[\,2mC\] done
clear
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question_answer45)
On decreasing the distance between the two charges of a dipole which is perpendicular to electric field and decreasing the angle between the dipole and electric field, the torque on the dipole
A)
increases done
clear
B)
decreases done
clear
C)
remains same done
clear
D)
cannot be predicated done
clear
View Solution play_arrow
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question_answer46)
Let \[\rho \left( r \right)=\frac{Q}{\pi {{R}^{4}}}r\] be the charge density distribution for a solid sphere of radius R and total charge Q. For a point ?P? inside the sphere at distance \[{{r}_{1}}\] from the center of the sphere, the magnitude of electric field is:
A)
\[\frac{Q}{4\pi {{\in }_{0}}{{R}_{1}}^{2}}\]\[\] done
clear
B)
\[\frac{Qr_{1}^{2}}{4\pi {{\in }_{0}}{{R}^{4}}}\] done
clear
C)
\[\frac{Qr_{1}^{2}}{3\pi {{\in }_{0}}{{R}^{4}}}\] done
clear
D)
\[0\] done
clear
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question_answer47)
In the figure the electric lines on the right have twice the separation of those on the left. If a charge particle takes time t to move a distance x in left region, then it will take time to travel the same distance in the right side region is:
A)
\[\frac{t}{2}\] done
clear
B)
\[t\] done
clear
C)
\[\sqrt{2}t\] done
clear
D)
\[2t\] done
clear
View Solution play_arrow
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question_answer48)
N identical point charges are kept summetrically on the periphery of the circle \[{{x}^{2}}+{{y}^{2}}={{R}^{2}}\]in xy plane. The resultant electric field at (0, 0, R) is \[{{E}_{1}}\] and at (0, 0, 2R) is \[{{E}_{2}}\]. The ratio of \[\frac{{{E}_{1}}}{{{E}_{2}}}\]is
A)
\[\frac{5\sqrt{5}}{4\sqrt{2}}\] done
clear
B)
\[\frac{5}{2}\] done
clear
C)
\[\frac{5}{4}\] done
clear
D)
\[\frac{5\sqrt{5}}{2\sqrt{2}}\] done
clear
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question_answer49)
Two point dipoles of dipole moment \[{{\vec{p}}_{1}}\]and \[{{\vec{p}}_{2}}\]are at a distance x from each other and \[{{\vec{p}}_{1}}||{{\vec{p}}_{2}}.\] The force between the dipoles is:
A)
\[\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{4{{p}_{1}}{{p}_{2}}}{{{x}^{4}}}\] done
clear
B)
\[\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{3{{p}_{1}}{{p}_{2}}}{{{x}^{4}}}\] done
clear
C)
\[\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{6{{p}_{1}}{{p}_{2}}}{{{x}^{4}}}\] done
clear
D)
\[\frac{1}{4\pi {{\varepsilon }_{0}}}\frac{8{{p}_{1}}{{p}_{2}}}{{{x}^{4}}}\,\] done
clear
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question_answer50)
Two identical electric dipoles are arranged on x-axis as shown in figure. Electric field at the origin will be
A)
Zero done
clear
B)
\[\frac{kp\sqrt{2}}{{{r}^{3}}}\hat{j}\] done
clear
C)
\[\frac{-kp\sqrt{2}}{{{r}^{3}}}\hat{j}\] done
clear
D)
\[\frac{-kp}{{{r}^{3}}}\hat{i}-\frac{-kp}{{{r}^{3}}}\hat{j}\] done
clear
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question_answer51)
A liquid drop having 6 excess electrons is kept stationary under a uniform electric field of\[25.5KV{{m}^{-1}}\]. The radius of the drop is (neglect buotany)
A)
\[4.3\times {{10}^{-7}}m\] done
clear
B)
\[7.3\times {{10}^{-7}}m\] done
clear
C)
\[0.078\times {{10}^{-7}}m\] done
clear
D)
\[3.4\times {{10}^{-7}}m\] done
clear
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question_answer52)
An electric dipole, consisting of two opposite charges of \[2\times {{10}^{-\,6}}C\] each separated by a distance 3 cm is placed in an electric field of \[2\times {{10}^{5}}N/C.\] Torque acting on the dipole is
A)
\[12\times {{10}^{-1}}N-m\] done
clear
B)
\[12\times {{10}^{-2}}N-m\] done
clear
C)
\[12\times {{10}^{-3}}N-m\] done
clear
D)
\[12\times {{10}^{-4}}N-m\] done
clear
View Solution play_arrow
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question_answer53)
Point charge q moves from point P to point S along the path PQRS (as shown in fig.) in a uniform electric field E pointing co-parallel to the positive direction of X-axis. The coordinates of the points P, Q, R and S are (a, b, 0), (2a, 0, 0), (a, -b, 0) and (0, 0, 0) respectively. The work done by the field in the above case is given by the expression
A)
\[qEA\] done
clear
B)
\[-qEA\] done
clear
C)
\[qEA\sqrt{2}\] done
clear
D)
\[qE\sqrt{\left[ {{\left( 2a \right)}^{2}}+{{b}^{2}} \right]}\] done
clear
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question_answer54)
A pendulum bob of mass m carrying a charge q is at rest with its string making and angle \[\theta \] with the vertical in a uniform horizontal electric field E. The tension in the string is
A)
\[\frac{mg}{\sin \theta }\text{ and }\frac{qE}{\cos \theta }\] done
clear
B)
\[\frac{mg}{\cos \theta }\text{ and }\frac{qE}{\sin \theta }\] done
clear
C)
\[\frac{mg}{\cos \theta }\text{ and }\frac{qE}{\sin \theta }\] done
clear
D)
\[\frac{mg}{qE}\] done
clear
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question_answer55)
Two very long line charges of uniform charge density \[+\lambda \]and \[-\lambda \]are placed along same line with the separation between the nearest ends being 2a, as shown in figure. The electric field intensity at point O is
A)
\[\frac{\lambda }{2\pi {{\varepsilon }_{0}}a}\] done
clear
B)
0 done
clear
C)
\[\frac{\lambda }{\pi {{\varepsilon }_{0}}a}\] done
clear
D)
\[\frac{\lambda }{4\pi {{\varepsilon }_{0}}a}\] done
clear
View Solution play_arrow
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question_answer56)
Figure shows an electric quadrupole, with quadruple moment \[(Q\text{ }=\text{ }2q{{\ell }^{2}}).\]The electric field at a distance from its center at the axis of the quadrupole is given by
A)
\[\left( \frac{1}{4\pi {{\in }_{0}}} \right)\frac{Q}{{{r}^{4}}}\] done
clear
B)
\[\left( \frac{1}{4\pi {{\in }_{0}}} \right)\frac{2Q}{{{r}^{4}}}\] done
clear
C)
\[\left( \frac{1}{4\pi {{\in }_{0}}} \right)\frac{3Q}{{{r}^{4}}}\] done
clear
D)
None of these done
clear
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question_answer57)
A spherical portion has been removed from a solid sphere having a charge distributed uniformly in its volume as shown in the figure. The electric field inside the emptied space is
A)
zero everywhere done
clear
B)
non-zero and uniform done
clear
C)
non-uniform done
clear
D)
zero only at its center done
clear
View Solution play_arrow
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question_answer58)
Find the electric field vector at P (a, a, a) due to three infinitely long lines of charges along the x, y and z- axes, respectively. The charge density, i.e., charge per unit length of each wire is \[\lambda .\]
A)
\[\frac{\lambda }{3\pi {{\varepsilon }_{0}}a}\left( \hat{i}+\hat{j}+\hat{k} \right)\] done
clear
B)
\[\frac{\lambda }{2\pi {{\varepsilon }_{0}}a}\left( \hat{i}+\hat{j}+\hat{k} \right)\] done
clear
C)
\[\frac{\lambda }{2\sqrt{2}\pi {{\varepsilon }_{0}}a}\left( \hat{i}+\hat{j}+\hat{k} \right)\] done
clear
D)
\[\frac{\sqrt{2}\lambda }{\pi {{\varepsilon }_{0}}a}\left( \hat{i}+\hat{j}+\hat{k} \right)\] done
clear
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question_answer59)
A particle of charge q and mass m moves rectilinearly under the action of electric field \[E=A-Bx,\]where A and B are positive constants and x is distance from the point where particle was initially at rest then the distance traveled by the particle before coming to rest and acceleration of particle at that moment are respectively:
A)
\[\frac{2A}{B},0\] done
clear
B)
\[0,-\frac{qA}{m}\] done
clear
C)
\[\frac{2A}{B},-\frac{qA}{m}\] done
clear
D)
\[\frac{-2A}{B},-\frac{qA}{m}\] done
clear
View Solution play_arrow
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question_answer60)
A ring of charge with radius 0.5 m has \[0.002\pi m\]gap. If the ring carries a charge of +1 C, the electric field at the center is
A)
\[7.5\times {{10}^{7}}N{{C}^{-1}}\] done
clear
B)
\[7.2\times {{10}^{7}}N{{C}^{-1}}\] done
clear
C)
\[6.2\times {{10}^{7}}N{{C}^{-1}}\] done
clear
D)
\[6.5\times {{10}^{7}}N{{C}^{-1}}\] done
clear
View Solution play_arrow
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question_answer61)
A point charge \[50\mu C\] is located in the x-y plane at a point whose position vector is \[\vec{r}=\left( 2\hat{i}+3\hat{j} \right)m.\]Then electric field at the point whose position vector is \[\vec{r}=\left( 8\hat{i}-5\hat{j} \right)m.\](in vector form) will be
A)
\[90\left( -3\hat{i}+4\hat{j} \right)V/m\]\[\] done
clear
B)
\[900\left( 3\hat{i}-4\hat{j} \right)V/m\] done
clear
C)
\[90\left( 3\hat{i}-4\hat{j} \right)V/m\] done
clear
D)
(d)\[900\left( -3\hat{i}+4\hat{j} \right)V/m\] done
clear
View Solution play_arrow
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question_answer62)
A thin glassrod is bent into a semicircle of radius r. A charge +Q is uniformly distributed along the upper half, and a charge -Q is uniformly distributed along the lower half, as shown in fig. The electric field E at P, the center of the semicircle, is
A)
\[\frac{Q}{{{\pi }^{2}}{{\varepsilon }_{0}}{{r}^{2}}}\] done
clear
B)
\[\frac{2Q}{{{\pi }^{2}}{{\varepsilon }_{0}}{{r}^{2}}}\] done
clear
C)
\[\frac{4Q}{{{\pi }^{2}}{{\varepsilon }_{0}}{{r}^{2}}}\] done
clear
D)
\[\frac{Q}{4{{\pi }^{2}}{{\varepsilon }_{0}}{{r}^{2}}}\] done
clear
View Solution play_arrow
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question_answer63)
A charge is situated at a certain distance from an electric dipole in the end-on position experiences a force F. If the distance of the charge is doubled, the force acting on the charge will be
A)
F/4 done
clear
B)
F/8 done
clear
C)
2F done
clear
D)
F/2 done
clear
View Solution play_arrow
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question_answer64)
The thickness of a flat sheet of metal foil is d, and its area is S.A charge q is located at a distance \[\ell \]from the centre of the sheet such that \[d<<\sqrt{S}<<l.\]Determine the force F with which the sheet is attracted to the charge q, assuming that the straight line connecting the charge to the center of the sheet. (Approximately)
A)
\[\frac{{{q}^{2}}Sd}{8{{\pi }^{2}}{{\varepsilon }_{0}}{{\ell }^{5}}}\] done
clear
B)
\[\frac{{{q}^{2}}Sd}{4{{\pi }^{2}}{{\varepsilon }_{0}}{{\ell }^{5}}}\] done
clear
C)
\[\frac{{{q}^{2}}Sd}{6{{\pi }^{2}}{{\varepsilon }_{0}}{{\ell }^{5}}}\] done
clear
D)
\[\frac{2{{q}^{2}}Sd}{3{{\pi }^{2}}{{\varepsilon }_{0}}{{\ell }^{5}}}\] done
clear
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question_answer65)
A thin conducting ring of radius R is given a charge +Q. The electric field at the center O of the ring due to the charge on the part AKB of the ring is E. The electric field at the center due to the charge on the part ACDB of the ring is
A)
E along KO done
clear
B)
E along OK done
clear
C)
E along KO done
clear
D)
3E along OK done
clear
View Solution play_arrow
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question_answer66)
A circular wire loop of radius x carries a total charge q distributed uniformly over its length. A small length dl of the wire is cut off. Find the value of m if \[\frac{qdl}{m{{\pi }^{2}}{{\varepsilon }_{0}}{{a}^{3}}}\]be the electric field a center due to remaining wire.
A)
5 done
clear
B)
6 done
clear
C)
3 done
clear
D)
8 done
clear
View Solution play_arrow
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question_answer67)
Three identical positive charges Q are arranged of the triangle is a. Find the intensity of the field at the vertex of a regular tetrahedron of which the triangle is the base.
A)
\[\sqrt{6}\frac{KQ}{{{a}^{2}}}\] done
clear
B)
\[\sqrt{2}\frac{KQ}{{{a}^{2}}}\] done
clear
C)
\[\sqrt{3}\frac{KQ}{{{a}^{2}}}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer68)
The electric field intensity at the center of a uniformly charged hemispherical shell is \[{{E}_{0}}.\]Now two portions of the remaining portion is shown in Fig. If \[\alpha =\beta =\pi /3\], then the electric field intensity at the center due to the remaining portion is
A)
\[{{E}_{0}}/3\] done
clear
B)
\[{{E}_{0}}/6\] done
clear
C)
\[{{E}_{0}}/2\] done
clear
D)
Information incomplete done
clear
View Solution play_arrow
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question_answer69)
Consider a uniform spherical charge distribution of radius \[{{R}_{1}}\] centered at the origin O. In this distribution, a spherical cavity of radius \[{{R}_{2}}\], centered at P with distance \[OP=a={{R}_{1}}-{{R}_{2}}\](see figure) is made. If the electric field inside the cavity at position \[\vec{r}\]is \[\vec{E}\overrightarrow{(r)}\], then the correct statement is
A)
\[\vec{E}\] is uniform, its magnitude is independent of \[{{R}_{2}}\]but its direction depends on \[\vec{r}\] done
clear
B)
\[\vec{E}\] is uniform, its magnitude depends on \[{{R}_{2}}\]and its direction depends on \[\vec{r}\] done
clear
C)
\[\vec{E}\] is uniform, its magnitude depends of a but its direction depends on \[\vec{a}\] done
clear
D)
\[\vec{E}\] is uniform and both its magnitude and direction depends on \[\vec{a}\] done
clear
View Solution play_arrow
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question_answer70)
A thin spherical shell of radius R has charge Q spread uniformly over its surface. Which of the following graphs most closely represents the electric field \[E\left( r \right)\]produced by the shell in the range \[0\le r<\infty ,\] where r is the distance from the center of the shell?
A)
B)
C)
D)
View Solution play_arrow
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question_answer71)
Find the force experienced by a semicircular rod having a charge q as shown in Fig. Radius of the wire is R, and the line of charge with linear charge density \[\lambda \] passes through its center and is perpendicular to the plane of wire.
A)
\[\frac{\lambda q}{2{{\pi }^{2}}{{\varepsilon }_{0}}R}\] done
clear
B)
\[\frac{\lambda q}{{{\pi }^{2}}{{\varepsilon }_{0}}R}\] done
clear
C)
\[\frac{\lambda q}{4{{\pi }^{2}}{{\varepsilon }_{0}}R}\] done
clear
D)
\[\frac{\lambda q}{4\pi {{\varepsilon }_{0}}R}\] done
clear
View Solution play_arrow
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question_answer72)
A particle of charge - q and mass m moves in a circle of radius r around an infinitely long line charge of linear charge density \[+\lambda .\]Then time period will be
A)
\[T=2\pi r\sqrt{\frac{m}{2k\lambda q}}\] done
clear
B)
\[{{T}^{2}}=\frac{4{{\pi }^{2}}m}{2k\lambda q}{{r}^{3}}\] done
clear
C)
\[T=\frac{1}{2\pi r}\sqrt{\frac{2k\lambda q}{m}}\] done
clear
D)
\[T=\frac{1}{2\pi r}\sqrt{\frac{m}{2k\lambda q}}\] done
clear
View Solution play_arrow
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question_answer73)
An electric dipole of moment \[\vec{P}\] is placed in a uniform electric field \[\vec{E}\]. If the dipole is slightly rotated about an axis perpendicular to the plane containing \[\vec{E}\] and \[\vec{P}\] passing through the center of the dipole, the dipole executes simple harmonic motion. Consider I to be the moment of inertia of the dipole about the axis of rotation. What is the time period of such oscillation?
A)
\[\sqrt{\left( pE/I \right)}\] done
clear
B)
\[2\pi \sqrt{\left( I/pE \right)}\] done
clear
C)
\[2\pi \sqrt{\left( I/2pE \right)}\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer74)
Two point dipoles \[p\hat{k}\] and \[\frac{P}{2}\hat{k}\] are located at (0, 0, 0) and (1m, 0, 2m) respectively. The resultant electric field due to the two dipoles at the point (1m, 0, 0) is
A)
\[\frac{9P}{32\pi {{\in }_{0}}}\hat{k}\] done
clear
B)
\[\frac{-7P}{32\pi {{\in }_{0}}}\hat{k}\] done
clear
C)
\[\frac{7P}{32\pi {{\in }_{0}}}\hat{k}\] done
clear
D)
\[\frac{6P}{{{\in }_{0}}}\hat{k}\] done
clear
View Solution play_arrow
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question_answer75)
The dipole moment of the given charge distribution is
A)
\[-\frac{4Rq}{\pi }\hat{i}\] done
clear
B)
\[\frac{4Rq}{\pi }\hat{i}\] done
clear
C)
\[-\frac{2Rq}{\pi }\hat{i}\] done
clear
D)
\[\frac{2Rq}{\pi }\hat{i}\] done
clear
View Solution play_arrow
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question_answer76)
The total electric flux emanating from a closed surface enclosing an \[\alpha -\]particle is (e-electronic charge)
A)
\[\frac{2e}{{{\varepsilon }_{0}}}\] done
clear
B)
\[\frac{e}{{{\varepsilon }_{0}}}\] done
clear
C)
\[e{{\varepsilon }_{0}}\] done
clear
D)
\[\frac{{{\varepsilon }_{0}}e}{4}\] done
clear
View Solution play_arrow
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question_answer77)
A point charge +Q is positioned at the center of the base of a square pyramid as shown. The flux through one of the four identical upper faces of the pyramid is
A)
\[\frac{Q}{16{{\varepsilon }_{0}}}\] done
clear
B)
\[\frac{Q}{4{{\varepsilon }_{0}}}\] done
clear
C)
\[\,\frac{Q}{8{{\varepsilon }_{0}}}\] done
clear
D)
\[0\] done
clear
View Solution play_arrow
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question_answer78)
Electric flux over a surface in an electric field may
A)
positive done
clear
B)
negative done
clear
C)
zero done
clear
D)
All of these done
clear
View Solution play_arrow
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question_answer79)
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
A)
\[\left( {{\phi }_{2}}+{{\phi }_{2}} \right)\times {{\varepsilon }_{0}}\] done
clear
B)
\[\left( {{\phi }_{2}}-{{\phi }_{2}} \right)\times {{\varepsilon }_{0}}\] done
clear
C)
\[\left( {{\phi }_{1}}+{{\phi }_{2}} \right)\times {{\varepsilon }_{0}}\] done
clear
D)
\[\left( {{\phi }_{1}}-{{\phi }_{2}} \right)\times {{\varepsilon }_{0}}\] done
clear
View Solution play_arrow
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question_answer80)
Electric charges are distributed in a small volume. The flux of the electric field through a spherical surface of radius 1 m surrounding the total charge is 100 V-m. The flux over the concentric sphere of radius 2 m will be
A)
25 V-m done
clear
B)
50 V-m done
clear
C)
100 V-m done
clear
D)
200 V-m done
clear
View Solution play_arrow
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question_answer81)
A loop of diameter d is rotated in a uniform electric field until the position of maximum electric flux is found. The flux in this position is measured to be \[\phi .\] What is the electric field strength?
A)
\[\frac{4\phi }{\pi {{d}^{2}}}\] done
clear
B)
\[\frac{2\phi }{\pi {{d}^{2}}}\] done
clear
C)
\[\frac{\phi }{\pi {{d}^{2}}}\] done
clear
D)
\[\frac{\pi \phi {{d}^{2}}}{4}\] done
clear
View Solution play_arrow
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question_answer82)
Consider an electric field \[\vec{E}={{E}_{0}}\hat{x}\] where \[{{E}_{0}}\] is a constant. The flux through the shaded area (as shown in the figure) due to this field is
A)
\[2{{E}_{0}}{{a}^{2}}\] done
clear
B)
\[\sqrt{2}{{E}_{0}}{{a}^{2}}\] done
clear
C)
\[{{E}_{0}}{{a}^{2}}\] done
clear
D)
\[\frac{{{E}_{0}}{{a}^{2}}}{\sqrt{2}}\] done
clear
View Solution play_arrow
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question_answer83)
The inward and outward electric flux for a closed surface in units of \[N-{{m}^{2}}/C\]are respectively \[8\times {{10}^{3}}\] and \[4\times {{10}^{3}}.\] Then the total charge inside the surface is [where \[{{\varepsilon }_{0}}\]= permittivity constant]
A)
\[4\times {{10}^{3}}C\] done
clear
B)
\[3.14\,\,N{{m}^{2}}/C\] done
clear
C)
\[\frac{(-\,4\times {{10}^{3}})}{\varepsilon }C\] done
clear
D)
\[-\,4\times {{10}^{3}}{{\varepsilon }_{0}}C\] done
clear
View Solution play_arrow
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question_answer84)
The electric field in a region of space is given by, \[\vec{E}={{E}_{0}}\hat{i}+2{{E}_{0}}\hat{j}\] where \[{{E}_{0}}=100N/C\]. The flux of the field through a circular surface of radius 0.02 m parallel to the Y-Z plane is nearly:
A)
\[0.125\,N{{m}^{2}}/C\] done
clear
B)
\[0.02\,N{{m}^{2}}/C\] done
clear
C)
\[0.005\,N{{m}^{2}}/C\] done
clear
D)
\[3.14\,\,N{{m}^{2}}/C\] done
clear
View Solution play_arrow
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question_answer85)
A solid sphere of radius R has a charge Q distributed in its volume with a charge density\[\rho =k{{r}^{a}}\], where k and an are constants and r is the distance from its center. If the electric field at \[r=\frac{R}{2}\] is \[\frac{1}{8}\] times that at \[r=R\], the value of a is.
A)
3 done
clear
B)
5 done
clear
C)
2 done
clear
D)
both [a] and [b] done
clear
View Solution play_arrow
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question_answer86)
A disc of radius a/4 having a uniformly distributed charge 6C is placed in the x-y plane with its center at (-a/2, 0, 0). A rod of length a carrying a uniformly distributed charge 8C is placed on the x-axis from \[x=a/4\] to \[x=5a/4\]. Two point charges -7C and 3C are placed at (a/4, -a/4, 0) and (-3a/4, 3a/4, 0), respectively. Consider a cubical surface formed by six surfaces \[x=\pm a/2,y=\pm a/2,z=\pm a/2.\] The electric flux through this cubical surface is
A)
\[\frac{-2C}{{{\varepsilon }_{0}}}\] done
clear
B)
\[\frac{2C}{{{\varepsilon }_{0}}}\] done
clear
C)
\[\frac{10C}{{{\varepsilon }_{0}}}\] done
clear
D)
\[\frac{12C}{{{\varepsilon }_{0}}}\] done
clear
View Solution play_arrow
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question_answer87)
A system consists of a uniform charged sphere of radius R and a surrounding medium filled by a charge with the volume density \[\rho =\frac{\alpha }{r},\] where \[\alpha \]a positive constant is and r is the distance from the center of the charge. The charge of the sphere for which the electric field intensity E outside the sphere is independent of r is-
A)
\[\pi {{R}^{2}}\alpha \] done
clear
B)
\[4\pi {{R}^{2}}\alpha \] done
clear
C)
\[2\pi {{R}^{2}}\alpha \] done
clear
D)
\[3\pi {{R}^{2}}\alpha /4\] done
clear
View Solution play_arrow
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question_answer88)
A charged particle q is placed at the center O of cube of length L (A B C D E F G H). Another same charge q is place at a distance L from O. Then the electric flux through ABCD is
A)
\[q/4\pi {{\in }_{0}}L\] done
clear
B)
zero done
clear
C)
\[q/2\pi {{\in }_{0}}L\] done
clear
D)
\[q/3\pi {{\in }_{0}}L\] done
clear
View Solution play_arrow
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question_answer89)
A sphere of radius R carries charge density \[\rho \]proportional to the square of the distance from the center such that \[\rho =C{{R}^{2}}\], where C is a positive constant. At a distance R/2 from the center, the magnitude of the electric field is
A)
\[\frac{C{{R}^{3}}}{20{{\in }_{0}}}\] done
clear
B)
\[\frac{C{{R}^{3}}}{10{{\in }_{0}}}\] done
clear
C)
\[\frac{C{{R}^{3}}}{5{{\in }_{0}}}\] done
clear
D)
\[\frac{C{{R}^{3}}}{40{{\in }_{0}}}\] done
clear
View Solution play_arrow
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question_answer90)
Figure shows a uniformly charged hemisphere of radius R. It has a volume charge density \[\rho .\] If the electric field at a point 2R, above its center is E, then what is the electric field at the point 2R below its center?
A)
\[\rho R/6{{\varepsilon }_{0}}+E\] done
clear
B)
\[\rho R/12{{\varepsilon }_{0}}-E\] done
clear
C)
\[-\rho R/6{{\varepsilon }_{0}}+E\] done
clear
D)
\[\rho R/12{{\varepsilon }_{0}}+E\] done
clear
View Solution play_arrow
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question_answer91)
A uniformly charged and infinitely long line having a linear charge density \[\lambda \] is placed at a normal distance y from a point O. Consider an imaginary sphere of radius R with O as center and R>y. Electric flux through the surface of the sphere is
A)
zero done
clear
B)
\[\frac{2\lambda R}{{{\varepsilon }_{0}}}\] done
clear
C)
\[\frac{2\lambda \sqrt{{{R}^{2}}-{{y}^{2}}}}{{{\varepsilon }_{0}}}\] done
clear
D)
\[\frac{\lambda \sqrt{{{R}^{2}}+{{y}^{2}}}}{{{\varepsilon }_{0}}}\] done
clear
View Solution play_arrow
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question_answer92)
Flux passing through the shaded surface of a sphere when point charge q is placed when a point charge q is placed at the center is (radius of the sphere is R)
A)
\[q/{{\varepsilon }_{0}}\] done
clear
B)
\[q/2{{\varepsilon }_{0}}\] done
clear
C)
\[q/4{{\varepsilon }_{0}}\] done
clear
D)
zero done
clear
View Solution play_arrow
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question_answer93)
In the figure the net electric flux through the area A is \[\phi =\vec{E}.\vec{A}\] when the system is in air. In immersing the system in water the net electric flux through the area
A)
becomes zero done
clear
B)
remains same done
clear
C)
increases done
clear
D)
decreases done
clear
View Solution play_arrow
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question_answer94)
A surface has the area vector \[\vec{A}=\left( 2\hat{i}+3\hat{j} \right){{m}^{2}}.\] The flux of an electric field through it if the field is \[\vec{E}=4\hat{i}\frac{V}{m}:\]
A)
8V-m done
clear
B)
12Vm done
clear
C)
20V-m done
clear
D)
zero done
clear
View Solution play_arrow
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question_answer95)
For a given surface the Gauss's law is stated as \[\oint{\vec{E}.dA=0.}\]From this we can conclude that
A)
E is necessarily zero on the surface done
clear
B)
E is perpendicular to the surface at every point done
clear
C)
the total flux through the surface is zero done
clear
D)
the flux is only going out of the surface done
clear
View Solution play_arrow
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question_answer96)
A charge q is placed at the center of the open end of a cylindrical vessel. The flux of the electric filed through the surface of the vessel is
A)
zero done
clear
B)
\[q/{{\varepsilon }_{0}}\] done
clear
C)
\[q/2{{\varepsilon }_{0}}\] done
clear
D)
\[2q/{{\varepsilon }_{0}}\] done
clear
View Solution play_arrow
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question_answer97)
The surface density on the copper sphere is \[\sigma .\]The electric field strength on the surface of the sphere is
A)
\[\sigma \] done
clear
B)
\[\sigma \,/2\] done
clear
C)
\[\sigma \,/2{{\varepsilon }_{0}}\] done
clear
D)
\[Q/{{\varepsilon }_{0}}\] done
clear
View Solution play_arrow
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question_answer98)
An electric dipole is put in north-south direction in a sphere filled with water. Which statement is correct?
A)
Electric flux is coming towards sphere. done
clear
B)
Electric flux is coming out of sphere. done
clear
C)
Electric flux is entering into sphere and leaving the sphere are same. done
clear
D)
Water does not permit electric flux to enter into sphere. done
clear
View Solution play_arrow
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question_answer99)
The magnitude of the average electric field normally present in the atmosphere just above the surface of the Earth is about 150 N/C, directed inward towards the center of the Earth. This gives the total net surface charge carried by the Earth to be: [Given \[{{\varepsilon }_{0}}=8.85\times {{10}^{-12}}{{C}^{2}}/N-{{m}^{2}},\]\[{{R}_{E}}=\]\[6.37\times {{10}^{6}}m\]] magnitude of the average electric field normally present in the atmosphere just above the surface of the Earth is about 150 N/C, directed inward
A)
+670kC done
clear
B)
-670kC done
clear
C)
-680kC done
clear
D)
+680kC done
clear
View Solution play_arrow
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question_answer100)
One-fourth of a sphere of radius R is removed as shown in Fig. An electric field E exists parallel to the xy plane. Find the flux through the curved part.
A)
\[\pi {{R}^{2}}E\] done
clear
B)
\[\sqrt{2}\pi {{R}^{2}}E\] done
clear
C)
\[\pi {{R}^{2}}E/\sqrt{2}\] done
clear
D)
None of these done
clear
View Solution play_arrow