Need Physics help!!!

[TheoPetro]

Im having a hell of a time with this phyics homework. If anyone knows a site with a forum and a LARGE community to answer simple questions fast post it.

thanks in advance

EDIT:

k heres the problem if anyone here knows.

In induction when you move a magnet to the right through a loop,

S---(loop)---N

how can you tell what the induced I is through the loop? im trying to use the right hand rule but its kicking my ass. The book sais something about the induced I's B field opposing the B field of the magnet. this isnt making much sense tho.

If anyone knows can you please tell me your reasoning because i dont get this at all.

 

[cirthix]

eh... here

 

[TheoPetro]

question added in OP

 

[PurdueRy]

thumb in direction in movement. Current moves in a direction to create a flux that opposes the change in flux created by the magnet. on its way into the coil the flux is increasing. Therefore point your thumb in the opposite direction of movement. Your fingers will curl in the direction of current. On the way out it will be the exact opposite

 

[TheoPetro]

im kinda understanding it now ive got another one tho (sorry im not trying to make ya do my homework or anything)


you want the Force needed to remove the rectangle,
.......................l <-- End of B field
X...X...X...X...X l
...l -------------- l---------------l
X l X...X...X...X l...................l
...l....................l....................l
X l X...X...X...X l...................l
...l -------------- l---------------l
X...X...X...X...X.l
.......................l

try to ignore periods

The rectangle is being pulled to the right at 3.40 m/s.
The B field .450T
R of wire is .230 ohms
Bottom of rectangle = .750cm
Side of rectangle = .350cm

 

[MikeMike]

friction is the worst thing ever.

 

[TheoPetro]

i tried to fix the picture didnt help much