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

Monjur Alahi

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?


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Salim Ahmed Kawsar

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Correct 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.

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