Quantum Nature of Charge
In Milikan's oil drop experiment , the charge present on an oil drop is ` 12.8 xx 10^(-18)C,` Calculate the number of electrons presents in oil drop.

Explanation

Here , ` Q = 12.8 xx 10 ^(-18) C `
` " " e= 1 .6 xx 10 ^(-19) C , n=? `
As,` " " Q = n e or n = (Q)/(e) `
` " " = (12.8 xx 10 ^(-18))/(1.6 xx 10 ^(-19)) =80 `
Hence , number of electrons presents on an oil drop is 80.