A point charge of `10^(-8) C` is situated at the origin of co-ordinatges. Find the potential difference between the points `A(4,4,2) and B(1,2,2)`.

Answer

`-15V`

Explanation

Here, `q = 10^(-8) C, vec(r_(A)) = 4 hat(i) + 4 hat(j) + 2 hat(k)`
so that `r_(A) = sqrt(4^(2) + 4^(2) + 2^(2)) = 6`
`vec(r_(B)) = 1 hat(i) + 2 hat(j) + 2 hat(k)`, so that
`r_(B) = sqrt(1^(2) + 2^(2) + 2^(2)) = 3`.
`V_(A) - V_(B) = (q)/(4pi in_(0)) [(1)/(r_(A)) - (1)/(r_(B))]`
`= 9xx10^(9)xx10^(-8) [(1)/(6) - (1)/(3)] = -15 V`