Chapter 17 . Electric Forces & Fields. Terms to Know. Electrostatics: Study of electric charge Charged object: has unequal #s of protons and electrons positively charged object negatively charged object Opposite charges: attract + and – Like charges: repel
Electric Forces & Fields
FBA = force of B exerting on A
F = electrostatic force
kc = Coulomb constant = 8.99×109 N· m2/C2
qA = the charge of particle A
qB = the charge of particle B
r = the distance between A and B
G = 6.67×10‒11 N·m2/kg2
The electron and proton of a hydrogen atom are separated, on average, by a distance of 5.3×10−11 m. Find the magnitude of the electric force and the gravitational force that each particle exerts on the other.
Consider three point charges at the corners of a triangle, as shown right, where q1=6.00×10-9 C, q2=-2.00×10-9 C,
and q3=5.00×10-9 C. Find the magnitude and
direction of the resultant force on q3.
(b) A third particle (+1.5 chargesμC) is added to the configuration. If it is located 3.0 cm directly beneath A, what is the new net force on A?
(Ex) (1) + - + (2) - + -
(3) - - - (4) + + +
Three charges lie along the x-axis. One positive charge, q1 = 15 µC, is at x = 2.0 m, and another positive charge, q2=6.0 µC, is at the origin. At what point on the x-axis must a negative charge, q3, be placed so that the resultant force on it (q3) is zero.