# Magnetic field question

1. Jan 15, 2015

### iverse

Puting a 150 micro.m tick coper tape into a magnetic fild of 0.65. The curent going through the tape = 23 A. What is the voltage on the edges of that tape ?

2. Relevant equations
I used this equation: U = dBS/dt
and then - > (B*r^2*pi*I)/e_0
3. The attempt at a solution
Resoult should be 7.4 microV

2. Jan 15, 2015

### Staff: Mentor

Just showing what the result should be is not enough; please show us what attempts you have made to obtain that result. We can't help you if we can't see what you have tried.

3. Jan 16, 2015

### iverse

What do you mean ? The resoult is not mine is from the book. Its what it should be not what i get. From the equation i put up i get totaly difrent stuff i dont even think its the right one. I hope someone can resolve this...

4. Jan 16, 2015

### iverse

Sorry * hmm i didn t even see it said the attempt :P. Its the actual resoult as i said.

5. Jan 16, 2015

### Staff: Mentor

So what do you get and how do you get it?

6. Jan 16, 2015

### iverse

I use the equation that i wrote. The resoult is realy irelevant cus it must be wrong but here it is.

B= 0.65 r = 0.75 * 10^-6 and I = 23 so -> (0.65 * (0.75*10^-6)^2 * pi * 23) / (1.6 * 10^-19) = 1.65 * 10^8 is what i get

7. Jan 16, 2015

### Staff: Mentor

Where did your Relevant equations come from, and what is their area of application? The information in your problem statement doesn't seem to pertain to the variables in those equations.

Hint: Look up "The Hall Effect".