Let `q_1` be a positive charge equal to the magnitude of the total charge on all electrons present in 0.9 mg of pure water and `q_2` be the charge on a 6.35 mg copper sphere from which 0.1% of its total electrons have been removed. Avogadro’s number, `N_A = 6 xx 10^(23)`
Molar mass of `H_(2)O = 18 g`
Molar mass of `Cu = 63.5 g`
(a) Find force between `q_1` and `q_2` if they are placed at a separation of 1 km. (b) How does this force compare with the weight of a car having mass of 1200 kg? What conclusion can you draw from the result?

Answer

(a). 120000N
(b). Force is nearly 10 times the weight of the car two conclusions can be drawn from the result-
(i). Electrostatic force is a strong force
(ii). One coulomb is a very large charge.