Coulomb's Law
Electric Fields
Dipoles
Distributed Charges
100
Charges A and B are placed a distance of 1.5m from one another. The charge of particle A is 0.003C whereas the charge of particle B is 0.006C. Charge B experiences an electrostatic force of Fb from charge A. Similarly, charge A experiences an electrostatic force of Fa from charge B.
What is the ratio of Fa to Fb?
1:1
100
What is the value of the electric field at point C?
Points A and B are point charges.
22.5 N/C in the −x direction
100
An electric dipole is formed from ±1.00nC charges spaced 4.00 mm apart. The dipole is at the origin, oriented along the x-axis. What is the electric field strength at the point given.
Part A
( x, y ) = ( 14.0 cm , 0 cm )
Express your answer with the appropriate units.
E = 26.23 N/c
100
Two 2.4-cm-diameter disks face each other, 1.9 mm apart. They are charged to ± 12 nC. What is the electric field strength at the midpoint between the centers of the disks?
E = 2.8×10^6 N/C
200
An excess charge of 10mC is put on an ideal neutral conducting sphere with radius 20cm. What is the Coulomb force this excess charge exerts on a point charge of 5mC that is 30cm from the surface of the sphere?
k=8.99∗109m2NC2
1.8 N
200
You are at point (0,5). A charge of −50nC is placed at the origin. What charge would you need to place at (0,-3) to cause there to be no net electric field at your location.
128 nC
200
The permanent electric dipole moment of the water molecule (H2O) is 6.2×10^−30 C⋅m
What is the maximum possible torque on a water molecule in a 3.6×10^8 N/C electric field?
2.23 x 10^-21 Nm
200
A small glass bead charged to 6.0 nC is in the plane that bisects a thin, uniformly charged, 10-cm-long glass rod and is 4.0 cm from the rod's center. The bead is repelled from the rod with a force of 780 μN. What is the total charge on the rod? 
37 nC