Electric Field

IMPORTANT

Electric Field: Overview

This topic covers concepts such as Electric Field, Inverse Square Law, Electric and Gravitational Field, Electric Field Due to a Point Charge, Electric Field Due to Two or More Charges, Electric Field at a Point in Vector Form, etc.

Important Questions on Electric Field

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A charge q is placed at the centre of the line joining two equal charges Q. The system of three charges will be in equilibrium if

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Consider a set of 12 equal charges (+q each), arranged to form two concentric regular hexagons in the xy-plane, centred at origin. The edges of the two hexagons have lengths a and 2a respectively. They are arranged in such a way that two vertices of each one of them are on the y-axis. Suppose that the charges from the vertices at (0,2a) and (0,-a) are removed. Then, the magnitude of the electric field produced by the resulting configuration at the origin is

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Consider two semi-infinite flat plates lying parallel to the x,y-plane at z=+d and z=-d, carrying uniform surface charge densities +σ and -σ, respectively. The plates extend from x=0 to x=- and from y=- to y=+. The direction of the electric field at a point whose coordinates are 0,0,2d is along

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In a conducting metallic sphere of radius 2r, an spherical cavity of radius r is made. A charge q is kept at the centre of the cavity as shown in the figure. Find the magnitude of the total electric field at 4r, 0, 0.

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Assertion: Due to two point charges electric field and electric potential cannot be zero at some point simultaneously.

Reason: Field is a vector quantity and potential is a scalar quantity.

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Two point charges q and 2q are placed some distance apart. If the electric field at the location of q be E, then that at the location of 2q will be

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Two equal positive charges q are placed at the vertices B and C of an isosceles triangle of base a and height h=33a2, as shown in the adjacent figure. When a charge q' is placed at A, it is found that at a point inside the triangle, the net electric field due to the three charges vanishes. If this point is at a height h3, then what is q'?

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The tracks of three charged particles in a uniform electrostatic field are shown in the figure. Which particle has the highest charge to mass ratio?
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If the flux of the electric field through a closed surface is zero then

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The constant k in Coulomb’s law depends on

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A metallic shpere is placed in a uniform electric field. The line of force follow the path(s) shown in the figure as,

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The maximum field intensity on the axis of a uniformly charged ring of charge q and radius R will be

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A thin conducting ring of radius R is given a charge +Q. 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 the part ACDB of the ring is

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The tracks of three charged particles in a uniform electrostatic field are shown in the figure. Which particle has the highest charge to mass ratio?

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Two point charges of 20 μC and 80 μC are 10 cm apart where will the electric field strength be zero on the line joining the charges from 20 μC charge

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A small metal ball is suspended in an uniform electric field with the help of an insulated thread. If a high energy X-ray beam falls on the ball, then the ball

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The electric intensity outside a charged sphere of radius R at a distance r(r>R) is

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The minimum strength of a uniform electric field that can tear a conducting neutral thin-walled sphere into two equal parts is known to be E0. Then determine the minimum electric field strength required to tear a sphere of one-fourth of the radius with the same wall thickness.

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Two mutually perpendicular infinitely long straight conductors carrying uniformly distributed charges of linear densities λ1 and λ2 are positioned at a distance r from each other.

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Force between the conductors depends on r as

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An electrostatic field line leaves at an angle α from point charge q1 and connects with point charge -q2 at an angle β(q1and q2 are positive) see figure below. If q2=32q1 and α=30°, then
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