Electromagnetic Induction Problem

AI Thread Summary
A 425 mA current is induced in a 48.0 cm wire moving through a magnetic field, with a magnetic force of 323 mN acting on it. The magnetic field strength was calculated to be approximately 1.58 T, and the voltage across the resistor was found to be 4.89 V. The velocity of the wire was determined to be about 6.43 m/s using the relationship between voltage, magnetic field, and velocity. The discussion highlights uncertainty regarding the direction of the induced current and the use of EMF in calculations. Clarification is sought on the EMF step and the implications of the positive voltage on direction.
paytona
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Homework Statement


A 425 mA conventional current is induced in a 48.0cm wire moved through a magnetic field. A 11.5 Ω resistor is connected to the wire as shown in the diagram below. If the magnetic force acting on the wire is 323 mN, then determine the direction and magnitude of the velocity of the wire moving through the magnetic field.
(Diagram is attached to this thread)

Homework Equations



B=F/IL
EMF=BlvsinΘ
V=IR

The Attempt at a Solution



My first step was to solve for the magnetic flux using B=F/IL
B= 323x10^-3 / (0.425A)(0.48m)
B= 1.5833333T

For my second step I found the Voltage of the current and resistor using V=IR
V=(0.425A)(11.5Ω)
V=4.8875V

For my third step I used V=Blv to solve for velocity
4.8875/[(1.583333T)(0.48m)= v
6.430934591m/s = v

and then I plugged it into the formula EMF=Blvsinθ
EMF=(1.58333)(0.48)(6.430934591)(sin90°)
EMF= 4.8875V

I know this is mostly wrong but I didn't know any other way to attempt this.
Please help!
 

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Why this doubt? I'd have done the same (except re-calculating emf at the end, perhaps).
Which step is tehe one you doubt the most ?
Apart from too many significant figures in the final answer, I do not see anything wrong in your solution.
 
BvU said:
Why this doubt? I'd have done the same (except re-calculating emf at the end, perhaps).
Which step is tehe one you doubt the most ?


Because I am missing direction. I feel I should use the voltage I get from solving for V as EMF to solve for velocity. I'm just very unsure about the actual EMF step and if the direction would be to right because the number is positive.
 
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