The distance between charges +q and −q is 2λ and between +2q and −2q is 4λ. The electrostatic potential at point P at a distance r from center O is -α[qlr2]×109V, where the value of α is _______ . (Use 14πε0=9×109 Nm2C-2) [2024]
(27)
V=KP→net·r→r3=9×109(6qℓ)r2cos(120°)
=-(27)(qℓr2)×109 Nm2C-2
⇒α=27