How does a current balance measure magnetic flux density?

[gabloammar]

That's just the length of the wire inside the magnet right?

The answer's 0.0078 T.

 

[wukunlin]

looks right doesn't it?

 

[gabloammar]

If B = 0.0078 T, then L has to equal 0.503 m, and I really don't know how that's supposed to come about. Unless of course the decimal in 5.0 is a misprint.

 

[wukunlin]

came out write when I did it, just check over your arithmetics

 

[gabloammar]

Using 1.962x10^-3 N for force, 0.50 A for current, and 5x10^-2 m for length, I get 7.85x10^-2 T, which isn't the right answer. :( How'd you get it right?

 

[wukunlin]

the mass is 0.02g

 

[gabloammar]

Haha, I took the 0.02 g correctly, I just didn't convert it correctly. Used x10^-2, must've pressed the wrong button. Got the correct answer!

But does this mean that I'm supposed to use the length of the wire that only passes through the magnet? [because only that can obviously be 5 cm]

 

[wukunlin]

yes, this force is produce only when the current is under the influence of a magnetic field, so outside the magnetic field there isn't this type of force (sorry for not clarifying this earlier)

 

[gabloammar]

Right, right, and right. Thank you SO much for your help. Life saver!
Good day. :)

 

[wukunlin]

no worries :)