71. In Millikan's experiment, a potential difference of 20k is applied between the two plates, which are 8 mm apart, to balance an oil drop of mass 4.9 × 10-14 ko Calculate the number of elementary charges on the drop (g = 10 m/s²). (7.6) m %3D , 106 mle enters a

Millikan measured the electron's charge by observing tiny charged oil drops in an electric field. Each drop had a charge imbalance of only a few electrons. The strength of the electric field was adjusted so that the electric and gravitational forces on a drop would balance and the drop would be suspended in air. In this way the charge on the drop could be calculated. The charge was always found to be a small multiple of 1.6e-19 C. Find the charge on an oil drop weighing 1.94  10-14 N and suspended in a downward field of magnitude 2.42  104 N/C. find E

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Coulomb’s law tells us that the electrostatic force between two charged objects can be calculated by: ?= ??1?2/?^2Where k is a constant with a value of 8.99x109 Nm2/C2; ?1 and ?2 are the charges of the two particles (1.602x10-19 C), and r is the distance between the two particles. The force is attractive if the charges of the two particles is opposite (one’s positive and one’s negative) and repulsive if the charges have the same charge (both positive or both negative). Calculate the electrostatic force on proton #1 from the other two protons.Will the gravitational force between the protons be attractive or repulsive? What about the electrostatic force? Which has the larger magnitude, the electrostatic force or the gravitational force? Can the electrostatic and gravitational forces alone create a stable Lithium nucleus?