A negatively charged particle called Negatron was discovered. In the Millikan's oil-drop experiment, the charges of the oil-drops in five experiments are reported as $3.2 \times 10^{- 19}$ coulomb; $4.8 \times 10^{- 19} c o u l o m b; 6.4 \times 10^{- 19} c o u l o m b$ .

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Solution

The Oil Drop Experiment
In 1909, Robert Millikan and Harvey Fletcher conducted the oil drop experiment to determine the charge of an electron. They suspended tiny charged droplets of oil between two metal electrodes by balancing downward gravitational force with upward drag and electric forces. The density of the oil was known, so Millikan and Fletcher could determine the droplets’ masses from their observed radii (since from the radii they could calculate the volume and thus, the mass). Using the known electric field and the values of gravity and mass, Millikan and Fletcher determined the charge on oil droplets in mechanical equilibrium. By repeating the experiment, they confirmed that the charges were all multiples of some fundamental value. They calculated this value to be $1.5924 \times 10^{- 19}$ Coulombs (C), which is within 1% of the currently accepted value of $1.602176487 \times 10^{- 19}$ C. They proposed that this was the charge of a single electron.

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Assume that Millikan performed the oil drop experiment. In the oil drop experiment, the following charges(in arbitrary units) were found on a series of oil droplets.

The data obtained is as follows:

2 $\times$ $10^{- 19}$ C
4 $\times$ $10^{- 19}$ C
6 $\times$ $10^{- 19}$ C

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6.48 \times 10^{- 19} C, 12.82 \times 10^{- 19} C, 19.3 \times 10^{- 19} C, 8.02 \times 10^{- 19} C, 25.62 \times 10^{- 19} C, 16.04 \times 10^{- 19} C,

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A negatively charged particle called Negatron was discovered. In the Millikan's oil-drop experiment, the charges of the oil-drops in five experiments are reported as 3.2×10−19 coulomb; 4.8×10−19coulomb;6.4×10−19coulomb.

A negatively charged particle called Negatron was discovered. In the Millikan's oil-drop experiment, the charges of the oil-drops in five experiments are reported as $3.2 \times 10^{- 19}$ coulomb; $4.8 \times 10^{- 19} c o u l o m b; 6.4 \times 10^{- 19} c o u l o m b$ .