Question

Find the electric force between two protons separated by a distance of 1 fermi (1 fermi = 10^-15 m). The protons in a nucleus remain at a separation of this order.

Answer 1

Charge on each proton = a= 1.6 × 10^–19 coulomb
Distance between charges = 10 × 10^–15 metre = r

= 9 × 2.56 × 10 = 230.4 Newton