Coulomb’s law, permittivity
constant
İ 0 = permittivity constant
Constantİ 0 = 8.85×10í^12 C^2 /N·m^2
What is the magnitude and
direction of the force the right
charge exerts on the left charge?
F = 18.0 N (to the left)
22.9 - Sample problem: electric vs. gravitational force
The two balls above are floating in deep space, with the only significant gravitational forces acting upon them being the ones they exert upon
one another. If they were electrically neutral, they would drift slowly together due to these forces and, after about an hour, come to rest against
each other.
You are asked to determine how many electrons should be added to each sphere so that the electrostatic force exactly counteracts the
gravitational force. You add the same number of electrons to each sphere, and disregard the change in mass of the spheres due to the added
electrons. It is negligible.How many excess electrons must be
added to each neutral lead sphere to
balance the force of gravity between
them?
(^408) Copyright 2000-2007 Kinetic Books Co. Chapter 22