# Electric Flux Question

1. Sep 2, 2004

### spatel600

Question 1: A 2cm x 3cm rectangle lies in the xz-plane. What is the electric flux through the rectangle if

E=(50i+100k) N/C

and

E=(50i+100j) N/C

Question 2:
A 1cm x 1cm x 1cm box is between the plates of a parallel-plate capacitor with two faces of the box perpendicular to E . The electric field strength is 1000 N/C.

What is the electric flux?

So far i have gotten .001
Any suggestions?

When it comes to the i,j,k stuff I always can never figure it out. Please help!!!

2. Sep 2, 2004

### elizabethg

hello, could u help me with my physics homework?

3. Sep 3, 2004

### HallsofIvy

Staff Emeritus
elizabethg: Please don't "hijack" someone else's thread. All homework questions should be posted in the appropriate homework forum- ask specific questions and show what you have done on the problem yourself.

SpateI600: The rectangle is in the x-z plane so only that part of the field in the y (or j) direction give flux through it.
In problem 1, E=(50i+100k) N/C which has NO j component- it is parallel to the rectangle and doesn't cross it. What does that tell you about the flux through the rectangle?

In problem2, E=(50i+100j) N/C. The j component is 100j N/C. Now think about what N and C mean and the area of the rectangle.