Answer:
Answer is 5.76×10^-25.
Step-by-step explanation:
Given values in the question are:
q = 1.6 x 10⁻¹⁹ C
k = 9 x 10⁹ N.m²/C²
Hence two points is 20mm apart so the radius becomes
R=0.02.
The formula is
F = kq^2/r^2
F= 9 x 10⁹× (1.6 x 10⁻¹⁹)^2 /(0.02)^2
F=5.76×10^-25.