## kym02 one year ago Help.

1. kym02

Sketch the field lines for the magnetic fields associated with the currents shown in the diagram below. (The dots and crosses show the direction of the currents.) WARNING: The drawing is a a bit crappy. sorry. :/ |dw:1397260188233:dw|

2. theEric

Hi! Do you know that the magnetic field "spins around" a wire? Well, the direction of the field at a point ((due to one wire)) is always perpendicular to the imaginary line that connects it to the wire. But perpendicular could be two ways. |dw:1397261007941:dw|

3. kym02

Quick question, is this related to the right hand grip rule?

4. theEric

Right!! Right hand rule. What you do is you take you're thumb. You point it in the direction of the current. Then you look how your fingers are curled. The magnetic field has that same curl!|dw:1397261214896:dw|

5. theEric

I assume that "x" is "into the screen."

6. kym02

and the dot out of the screen?

7. theEric

You try! :)

8. theEric
9. theEric

Now, magnetic field vectors add. So you'll see that |dw:1397261439666:dw||dw:1397261494265:dw|

10. theEric

And|dw:1397261563303:dw|will turn into

11. theEric

|dw:1397261630895:dw|

12. kym02

ahh now i understand! :) what does that arrow in between the dot and the cross represent?

13. theEric

You'll need to put these together or re-apply these concepts for you're bigger picture! :) The big arrow, here?|dw:1397261722560:dw|That's because the electric fields add, there, to be EXTRA strong! Between two of the same kind, however, the field CANCELS because they're in opposite directions. It's like \((1)+(-1)=0\)

14. kym02

ohhh woah you made it so easy.

15. theEric

I have to go. Good luck! I'm glad! :)

16. kym02

Thanks a lot!