(a) E = KQ1/R₁²
(b) V = KQ1/R1
Explanation:
Given -
Radius of the sphere = R1
Charge of the sphere = Q1
(a)
Electric field created by a point charge can be expressed as
E = q/4π∈₀r² = Kq/r²
Where, ∈₀ is the permittivity of free space
r is the distance between the charge and the point
K = 1/4π∈₀ = 9 X 10⁹ Nm²/C² (Coulomb's constant )
Therefore, the electric field at the surface of the sphere is:
E = KQ1/R₁²
(b)
The electric potential due to a point charge at a point is given by
V = q/ 4π∈₀r = Kq/r
Therefore, the electric potential at the surface of the sphere is
V = KQ1/R1
