Question

What value must q2 have if the electric potential at point a is to be zero?

Answer 1

To make the electric potential at point a zero, the electric potential due to q2 must be equal in magnitude but opposite in sign to the electric potential due to q1.

Step-by-step explanation:

To make the electric potential at point a zero, the electric potential due to q2 must cancel out the electric potential due to other charges. The electric potential due to a point charge at a distance r can be calculated using the equation V = k*q/r, where V is the electric potential, k is the electrostatic constant (9 x 10^9 Nm²/C²), q is the charge, and r is the distance. Therefore, to make the electric potential at point a zero, the electric potential due to q1 must be equal in magnitude but opposite in sign to the electric potential due to q2. Mathematically, this can be represented as:

Vq1 = - Vq2

Substituting the values, we have:

k*q1/r1 = - k*q2/r2

Simplifying the equation, we get:

q2 = - (q1 * r2) / r1

Answer 2

let r be side of square
V (B) = k q2/r + k Q / sqrt[r^2 + r^2] = 0 given
q2/r + Q / r root2 = 0
q2 = - Q / root2
q2/Q = - 1/root2
q2/Q = - root2 /2 = - 0.707

q2 equals negative 0.707 times Q