Doubts
Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents
Sign in to save progress →
Doubts
Sign in

Electrostatics question

2019 · 9 Jan · Shift 2 · Q56
Guest · try one question or challengeGuest · try one question or challenge
  1. PYQ Library
  2. /JEE Main
  3. /Physics
  4. /Electrostatics
  5. /2019 · 9 Jan · Shift 2 · Q56

Electrostatics question

2019 · 9 Jan · Shift 2 · Q56

JEE MainPhysicsElectrostaticsMCQ+4 / −1
Charge is distributed within a sphere of radius R with a volume charge density ρ(r)=Ar2e−2rs,\rho \left( r \right) = {A \over {{r^2}}}{e^{ - {{2r} \over s}}},ρ(r)=r2A​e−s2r​, where A and a are constants. If Q is the total charge of this charge distribution, the radius R is :
  1. A
    a log (1−Q2πaA)\left( {1 - {Q \over {2\pi aA}}} \right)(1−2πaAQ​)
  2. B
    a2{a \over 2}2a​ log (11−Q2πaA)\left( {{1 \over {1 - {Q \over {2\pi aA}}}}} \right)(1−2πaAQ​1​)
  3. C
    a log (11−Q2πaA)\left( {{1 \over {1 - {Q \over {2\pi aA}}}}} \right)(1−2πaAQ​1​)
  4. D
    a2{a \over 2}2a​ log (1−Q2πaA)\left( {1 - {Q \over {2\pi aA}}} \right)(1−2πaAQ​)
PreviousNext

More from Electrostatics

  • Two point charges q1 (10​μC) and q2(− 25 μ C) are placed on the x-axis at x = 1 m and x = 4 m respectively. The electric field (in V/m) at a point y = 3 m on y-axis is, [take ${1 \over {4\pi { \in…2019 · MCQ
  • A uniformly charged ring of radius 3a and total charge q is placed in xy-plane centred at origin. A point charge q is moving towards the ring along the z-axis and has speed u at z = 4a. The minimum value of u such that it crosses the…2019 · MCQ
  • In free space, a particle A of charge 1 μ C is held fixed at a point P. Another particle B of the same charge and mass 4 μ g is kept at a distance of 1 mm from P. If B is released, then its velocity at a distance of 9 mm from P is…2019 · MCQ
  • A charge Q is distributed over three concentric spherical shells of radii a, b, c (a < b < c) such that their surface charge densities are equal to one another. The total potential at a point at distance r from their common centre,…2019 · MCQ
  • Two electric dipoles, A, B with respective dipole moments dA​=−4qai and dB​=−2qai are placed on the x-axis with a separation R, as shown in the figure. The distance from A at which both of… Includes diagram2019 · MCQ
  • Charges –q and +q located at A and B, respectively, constitude an electric dipole. Distance AB = 2a, O is the mid point of the dipole and OP is perpendicular to AB. A charge Q is placed at P where OP = y and y >> 2a. The charge Q… Includes diagram2019 · MCQ
  • Four equal point charges Q each are placed in the xy plane at (0, 2), (4, 2), (4, –2) and (0, –2). The work required to put a fifth charge Q at the origin of the coordinate system will be -2019 · MCQ
  • The given graph shows variation (with distance r form centre) of : Includes diagram2019 · MCQ