GENERAL KNOWLEDGE

Detailed explanation-1: -Robert Millikan’s oil drop experiment provided the first clear measurement of the fundamental electric charge and thus helped cement the notion that nature is “grainy” at the smallest level. The first results came out in 1910, but the seminal work was a 1913 paper in the Physical Review.

Detailed explanation-2: -Millikan used the information to calculate the charge of an electron. He determined the charge to be 1.5924×10−19C, where C stands for coulomb, which is one ampere*second. Today, the accepted value of the charge of an electron is 1.602176487×10−19C.