Question

If g_E and g_M are the accelerations due to gravity on the surfaces of the earth and the moon respectively and if Millikan’s oil drop experiment could be performed on the two surfaces, one will find the ratio 

(electronic charge on the moon)/(electronic charge on the earth) to be
(a) g_M /g_E 

(b) 1

(c) 0 

(d) g_E /g_M

Answer 1

(b) : Since electronic charge (1.6 × 10^–19C) universal constant. It does not depend on g.
Therefore,Electronic  charge on the moon = electronic charge on the earth

or (electronic charge on the moon)/(electronic charge on the earth) = 1.