consider an atom with atomic number z as consisting of a positive point charge at the centre and surrounded by - Physics - Electric Charges And Fields

Question

consider an atom with atomic number z as consisting of a positive
point charge at the centre and surrounded by a distribution of
negative electricity uniformly distributed within a sphere of
radius R the electric field at apoint inside the atom at a distance
r from the centre is? please show the process
1) Ze/(4πεr^2 )×(1/r^2 – r/R^3)
2)zero

Neha Gupta · Accepted Answer

Let us suppose this is the case of solid sphere with uniform distribution of charge
R is the radius of the charge
volume charge density ρ = Q4πR3/3 = -3Ze4πR3now consider an inside point at distance r from the centre
according to gauss law:∫E
ds = charge enclosedε0E =charge enclosedarea×ε0 = charge enclosed4πr2ε0now charge enclosed = positive charge at centre + charge enclosded in the volume 4πr3/3 charge enclosded in the volume 4πr3/3  = ρ×4πr3/3 =-3Ze4πR3×4πr3/3 = -Zer3R3 E = -Zer3R3+ze4πr2ε0 = Ze4πε01r2-rR3