Question

calculate the electrical potential at a point P a distance of 1 m from either two to charge of +10 micro coulomb and -5 micro coulomb which are 10 cm apart calculate also the potential energy of a +2 micro coulomb charge placed at a point p​

Answer 1

a) V = 45 10³ V, b) U = 4.59 J

Step-by-step explanation:

a) The electric potential for a series of point charges is

V = k ∑
`(q_i)/(r_i)`

in this case point P is at a distance of 1 m from each charge, so the point is located perpendicular to the charges at its midpoint

V = k (
`(q_1)/(r) + (q_2)/(r)`)

V = 9 10⁹ (10 - 5/ 1) 10⁻⁶

V = 45 10³ V

b) the potential energy is

U = k (
`(q_1q)/(r) + (q_2q)/(r) + (q_1q_2)/(r_2)` )

where r = 1m and r₂ is the distance between the two charges r₂ = 0.10 m

U = 9 10⁹ (10 2 / 1 - 5 2/1 - 10 5 /0.10) 10⁻¹²

U = 9 10⁻³ 510

U = 4.59 J