Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
AP EAMCET2007PhysicsElectrostatics

Two unit negative charges are placed on a straight line. A positive charge q is placed exactly at the mid point between these unit charges. If the system of these three charges is in equilibrium, the value of q (in C ) is

Options

  1. A1.0
  2. B0.75
  3. C0.5
  4. D20 ~cm

Correct answer

D. 20 ~cm

Step-by-step solution

For equilibrium, we have F_ A B +F_ A C =0 or 1 4 ₀ q₁ q (d / 2)^2 + 1 4 ₀ q₁ q₂ d^2 =0 Given, q₁=q₂=-1 C So, - q (d / 2)^2 + 1 d^2 =0q= 1 4 =0.25 C

Practice Electrostatics on Quantrex Academy →

More from Electrostatics

A charge of 5 C is placed at the centre of a spherical shell S₁ of radius 10 cm. Now this system is enclosed inside another spherical shell S₂ of radius 20 cm. The ratio of the ele 2026Two point charges P = +25 C and Q = -16 C are placed 5 cm apart. Find the position of the point at which the resultant electric field is zero: 2026Bodies P, Q, R, S are labelled as having charges Q_P = 0.5 10⁻¹⁹C , Q_Q = 0.7 10⁻¹⁹C , Q_R = 2.1 10⁻¹⁹C , Q_S = 4.8 10⁻¹⁹C respectively. Select the body having the correct charge. 2026Uniform electric field of 5 10^3 ,NC⁻¹ is maintained in the positive Y direction. Now a point charge of 2 10⁻⁴C at rest is released from the origin. The kinetic energy attained by 2026A pith ball of mass 'm' gram and charge 'Q' is suspended using a mass less silk thread near a large charged conducting metal sheet of area 'A' and surface charged density ' '. If t 2026In a uniform electric field 10^6 N C⁻¹ an electric dipole of length 4 cm is placed with its axis making an angle 60^ with the electric field. If the dipole experiences a torque of 2026An electric field and magnetic field 1.8 10^4 Vm⁻¹ and 6 10⁻³ T respectively are applied simultaneously on an electron beam such that path of the beam remains undeviated, then the 2026A uniform electric field E = 3 i + 6 j + k passes through a closed cuboidal surface. One face of the cuboid has an area 4 m^2 and an outward unit normal given by 2 i +2 j +3 k 17 . 2026 Full Electrostatics list All AP EAMCET PYQs