Name: _______________________

# Quiz 3

02/17/2006

Ch. 18

Useful Numbers:  k=8.99x109 N m2/C2

1)      2 charges are placed at the base corners of an isosceles triangle with 3m sides and 2m base:  -4mC at bottom left and  +2mC at the bottom right.

a) What is the total electric field at the top corner of the triangle?

b) What would the force be on a -4mC charge placed at the top corner of the triangle?

2)      Three charged conducting balls are initially separated.  Sphere A has a charge of ‑80nC, Sphere B has a charge of 32nC, and Sphere C has a charge of 12nC.

a) Spheres A and B are brought into contact and then separated.  What are the charges on the 3 spheres?

b) Next, Spheres B and C are brought into contact and then separated.  What are the charges on the 3 spheres?

c) Next, Spheres A and B are brought into contact and then separated.  What are the charges on the 3 spheres?

d) Finally, Spheres A, B, and C are all brought into contact and then separated.  What are the charges on the 3 spheres?

 Sphere A Sphere B Sphere C Initial Charge -80nC 32nC 12nC a) b) c) d)