## anonymous one year ago Generator effect quesion

1. anonymous

its the hand rules kinda confused

2. anonymous

|dw:1437531616981:dw|

3. anonymous

which will become neagtive ? or b ? and its a electron flow

4. anonymous

A or B?

5. anonymous

Hmmm, I don't quite understand the illustration. What's happening?

6. anonymous

its going from north to south

7. anonymous

the v is the thumb

8. anonymous

What's going from north to south? Thumb? I think I'm missing some information.

9. anonymous

u know that hand rules?

10. anonymous

I do. The right hand rule is the name given to a few different things. In Electricity and Magnetism (E and M, or EnM, for short), it usually refers to pointing your thumb in the direction of the positive current, and your fingers will curl around in the direction of the magnetic field.

11. anonymous

Using your right hand, of course.

12. anonymous

its an electron so i thought it was left hand?

13. anonymous

Another version of the right hand rule involves pointing fingers in the direction of vectors in a cross product. You can then find the direction of the result by doing this. Example: A x B = C (A cross B) If you point your index finger in the direction of A (keeping the index finger straight), and your middle finger in the direction of B (flip your hand if you need to point in a direction on the back side of your hand), then the result of the cross product will be in the direction your thumb is pointing (if using the right hand).

14. anonymous

Correct, you can do the same thing with your left hand for an electron (negative current)

15. anonymous

for me i am getting B as positive am i correct?

16. anonymous

I can't say. I'm not sure what's happening in the picture.

17. anonymous

since it goes from + to -

18. anonymous

|dw:1437534462978:dw|

19. anonymous

this is what my hands look like

20. anonymous

left hand

21. anonymous

What is V?

22. anonymous

here is how the answr looks like

23. anonymous

24. anonymous

OH! A conductor is moving upwards between the magnets! I see!

25. anonymous

the answer is showing the electron is moving to the negtive side?

26. anonymous

how is that possible

27. anonymous

It's saying that a negative charge would build up on that side, because the electrons would move that direction.

28. anonymous

the electron is the thumb right

29. anonymous

the v is the fingers

30. anonymous

and the palm is the north to south field right?

31. anonymous

One sec. I just accidentally closed this window and had a LOT typed out, haha

32. anonymous

For this, we use the cross product hand rules. $\vec{F} = q\vec{\rm{v}}\times \vec{B}$ q is the charge of the particle. For an electron, this is a negative number. We can account for this by using our left hand. Since v comes first in the equation, we point our index finger in it's direction (upwards). Keep the hand aligned with the index finger, as much as you can. B comes next. We'll point the middle finger in the direction of B (to the right-ish). Then, stick out your thumb. Your thumb should be pointing towards B (back toward you-ish) This doesn't tell you the magnitude of the force, but your thumb is pointing in the direction of the force on the electron. Electrons would move towards point B, causing that side of the rod to become negatively charged.

33. anonymous

r there more these types of problems online?

34. anonymous

Specifically like this one? Or just EnM type problems in general?

35. anonymous

actually i think i understand these now nvm ,

36. anonymous

Excellent :)

37. anonymous

i am going to do more probs

38. anonymous

r u gonna stay here for a while?

39. anonymous

I actually need to leave for the night.