Question

The charge of an electron was first measured by the American physicist Robert Millikan during 1909–1913. In his experiment, oil was sprayed in very fine drops (about 10−4 mm in diameter) into the space between two parallel horizontal plates separated by a distance d. A potential difference VAB was maintained between the plates, causing a downward electric field between them. Some of the oil drops acquired a negative charge because of frictional effects or because of ionization of the surrounding air by x rays or radioactivity. The drops were observed through a microscope.

Calculate the charge qq of drop 4.

Answer 1

The charge of drop 4 in Millikan's oil-drop experiment can be calculated through careful measurements of the electric field strength and other variables. Unfortunately, the necessary data is not provided in the question. However, based on Millikan's findings, the charge of drop 4 would likely be -1.6 x 10^-19 C, the charge of an electron.

Step-by-step explanation:

The charge of drop 4 can be calculated using Millikan's oil-drop experiment. In this experiment, oil droplets are sprayed into a space between two charged plates, and their downward movement is observed using a microscope. By adjusting the electric field strength and making precise measurements, the charge on individual drops can be determined.

To calculate the charge of drop 4, the electric field strength and all relevant measurements need to be known. Unfortunately, the question does not provide the necessary data to perform the calculation.

In Millikan's original experiments, he found that the charge of individual oil drops was quantized in units of -1.6 x 10^-19 C, which is the charge of an electron. Therefore, it can be assumed that drop 4 would also have a charge of -1.6 x 10^-19 C if the experiment were conducted under similar conditions.