
#1
Jan1912, 05:41 AM

P: 14

"An electric conductor carrying electric current from left to right is placed in a downward magnetic field. It is observed that there are positive charge on the front of the conductor and negative charge a the back. If the electric current is reverse, flowing from right to left, then the positive charge will appear at the back and negative charge will appear at the front. Determine either negative or positive the free moving charge within the conductor is. "
What kind of phenomenon that cause charge to move at the back and front of the conductor? It does not seem like induction:( Thank you guys so much for helping:) 



#2
Jan1912, 08:17 AM

Mentor
P: 11,450





#3
Jan1912, 08:22 AM

Emeritus
Sci Advisor
HW Helper
PF Gold
P: 7,419

So, you need to determine the sign of the dominant charge carrier in the conductor? The phenomenon about which you inquired is: [itex]\vec{F}=q\vec{v}\times\vec{B}\,.[/itex] 



#4
Jan1912, 08:31 AM

P: 14

Electric Current
Thanks, Sammy:D I thought about that formula earlier and there's definitely some force that push the conductor to the front(or to the back). But I still can not figure out its relation with this part It is observed that there are positive charge on the front of the conductor and negative charge a the back. If the electric current is reverse, flowing from right to left, then the positive charge will appear at the back and negative charge will appear at the front.
P/S: PF is so heplful^^ I look up here many times for problems and this is the first time I can not find :D 



#5
Jan1912, 09:09 AM

Emeritus
Sci Advisor
HW Helper
PF Gold
P: 7,419

P/S: I wish that more users of PF would look things up. They often post threads inquiring about problems that have been answered the previous day. We are glad to hear that you find PF helpful. 



#6
Jan1912, 09:12 AM

Mentor
P: 11,450





#7
Jan1912, 09:27 AM

P: 14

I get it, it's a negativecharge carrier. Sorry gneill, I can't believe I miss your post...
Thank you both so much for helping! 


Register to reply 
Related Discussions  
Finding electric field/displacement current for timevarying current in coaxial cable  Advanced Physics Homework  0  
Finding electric field intensity, power, current given current density  Advanced Physics Homework  0  
probability current versus electric current  Quantum Physics  6  
whats the difference between an electric field and an electric current?  General Physics  3  
Electric current and direct current circuits  Introductory Physics Homework  14 