817.2 The calculation of the electric potential Choose voa=K(o=0, the electric potential of a point charge o is V(r=. or v(r) 0 817.2 The calculation of the electric potential Note (i)It is obviously that when r-yo0, v approaches 0. (iithe electric potential varies inversely the distance r to the first power, and the electric field varies inversely the distance r to the second power (ii) the electric potential is scalar, the electric field is vector5 Choose Vf =V(rf )=V(∞)=0, the electric potential of a point charge Q is r Q V r r Q V r i i 0 0 4 ( ) 4 ( ) πε πε = or = + Q x y V(r) − Q §17.2 The calculation of the electric potential (i)It is obviously that when r→∞, V approaches 0. (ii)the electric potential varies inversely the distance r to the first power, and the electric field varies inversely the distance r to the second power. (iii) the electric potential is scalar, the electric field is vector. Note: §17.2 The calculation of the electric potential