NEETPhysicsElectrostaticsMCQ+4 / −1
Four point charges Q, q, 2q and 2Q are placed, one at each corner of the square. The relation between Q and q for which the potential at the centre of the square is zero is
- AQ = q
- BQ =
- CQ = q
- DQ =
View written solutionFree
Correct answer: A
Let the side length of square be 'a' then potential at centre O is

= – Q – q + 2q + 2Q = 0 = Q + q = 0
Q = – q
More from Electrostatics
- Three charges, each +q, are placed at the corners of an isosceles triangle ABC of sides BC and AC, 2. D and E are the mid points of BC and CA. The work done in taking a charge Q from D to E is Includes diagram2011 · MCQ
- The electric potential V at any point (x, y, z), all in metres in space is given by V = 4x2 volt. The electric field at the point (1, 0, 2) in volt/meter, is2011 · MCQ
- Four electric charges +q, +q, q and q are placed at the corners of a square of side 2L (see figure). The electric potential at point A, midway between the two charges + q and +q, is Includes diagram2011 · MCQ
- A charge Q is enclosed by a Gaussian spherical surface of radius R. If the radius is doubled, then the outward electric flux will2011 · MCQ
- The electric field at a distance from the centre of a charged conducting spherical shell of radius R is E. The electric field at a distance from the centre of the sphere is2010 · MCQ
- A square surface of side L meter in the plane of the paper is placed in a uniform electric field (volt/m) acting along the same plane at an angle with the horizontal side of the square as shown in figurre. The electric flux… Includes diagram2010 · MCQ
- Two positives 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 on an electron)2010 · MCQ
- The electric potential at a point (x, y, z) is given by V = x2y xz3 + 4 The electric field at that point is2009 · MCQ