In an oil drop experiment, the following data were recorded :
Plate separation = 15 mm, Distance of fall = 10 mm
Potential difference = 3.2 kV, Viscosity of air = `1.82 xx 10^(-5)` Ns `m^(-2)`
Sucessive times of rise of the drop = 42 s and 78 s.
Radius of drop = `2.76 m xx 10^(-6) m`
Calculate the change in charge on the drop between the two sets of observation. To how many electrons does this correspond ?
