Airborne COVID-19 drops in electric fields. One of the major concerns with the COVID-19 pandemic is the transmission of the virus due to the water drops that are projected by sneezing, coughing, singing, talking, or even breathing. The larger drops soon settle out due to the gravitational force but drops with radii smaller than 5 um might remain suspended by air currents, posing a danger to anyone breathing them. However, common electric fields might remove some of them. Suppose a water drop with radius r - 1.51 μm and charge (-3.00 x 10 )e is near a flat plastic surface with surface charge density of +7.57 nC/m², as can commonly occur in homes. What are the magnitudes of (a) the Coulomb force and (b) the gravitational force that act on the drop? (a) Number (b) Number Units Units

Airborne COVID-19 drops in electric fields. One of the major concerns with the COVID-19 pandemic is the transmission of the virus due to the water drops that are projected by sneezing, coughing, singing, talking, or even breathing. The larger drops soon settle out due to the gravitational force but drops with radii smaller than 5 um might remain suspended by air currents, posing a danger to anyone breathing them. However, common electric fields might remove some of them. Suppose a water drop with radius r - 1.51 μm and charge (-3.00 x 10 )e is near a flat plastic surface with surface charge density of +7.57 nC/m², as can commonly occur in homes. What are the magnitudes of (a) the Coulomb force and (b) the gravitational force that act on the drop? (a) Number (b) Number Units Units

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter7: Electric Potential

Section: Chapter Questions

Problem 75P: The probability of fusion occurring is greatly enhanced when appropriate nuclei are brought close...

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