Question

1. A charge (uniform linear density=9.0 nC/m) is distributed along the x-axis from x=0 to x=3.0m. Determine the magnitude of the electric field at a point on the x axis with x=4.0m.

a)81 N/C
b)74 N/C
c)61 N/C
d)88 N/C
e)20 N/C

2. A +2nC point charge is placed at one corner of a square (1.5m on a side), and a -3.0nC charge is placed on a corner diagonally away from the first charge. What is the magnitude of the electric field at either of the two unoccupied corners?

a)20 N/C
b)14 N/C
c)4 N/C
d)12 N/C
e)8 N/C

Answer 1

2. What is Pythagoras theorem? figure the E from each, then use the theorem.

1. Simple integration. draw the figure.

E=int k (9.0E-9)/(4-x)^2 dx
integrate from x=0 to 3