What is the force between two small charged spheres having charges of 2 × 10−7 C and 3 × 10−7 C placed 30 cm apart in air

What is the force between two small charged spheres having charges of 2 × 10⁻⁷ C and 3 × 10⁻⁷ C placed 30 cm apart in air?

Solution:

Given that

Charge on the first sphere, q₁ = 2 × 10⁻⁷ C

Charge on the second sphere, q₂ = 3 × 10⁻⁷ C

Distance between the spheres, r = 30 cm =30/100 m = 0.3 m

(divide by 100 to convert cm to m )

Apply Coulomb’s law

q₁ = first charge

q₂ = Second charge

r = distance between both charge

ε₀= permittivity of free space

1/4πε0 = 9 × 10⁹ Nm²C^-2

Plug the values in formula we get 

Answer

Attraction force between both charges is 6 × 10⁻³ N.