Physics · Electric potential and its calculation for a point charge, electric dipole and system of charges
Three charges and are located at the vertices of an equilateral triangle. At the
Three charges \( 2 q,-q \) and \( -q \) are located at the vertices of an equilateral triangle. At the centre of the triangle:
- A. the field is zero but potential is non-zero
- B. the field is non-zero, but potential is zero
- C. both field and potential are zero
- D. both field and potential are non-zero
Step-by-step solution
At the centroid of an equilateral triangle, all vertices are equidistant. The potential is the scalar sum V = k/r * (2q - q - q) = 0. The electric field vectors from the two -q charges cancel horizontally, but their vertical components add with the field from the +2q charge, resulting in a net downward field of magnitude 3kq/r^2. Thus field is non-zero, potential is zero.
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