- #1
flyingpig
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Homework Statement
The square loop in the figure below is made of wires with a total series resistance of 10.0. It is placed in a uniform 0.100 T magnetic field directed perpendicular into the plane of the paper. The loop, which is hinged at each corner, is pulled as shown until the separation between points A and B is 3 m. If this process takes 0.100 s, what is the magnitude and direction of the average current generated in the loop?
The Attempt at a Solution
R = 10.0Ω
B = 0.100T
l = 3.00m
t = 0.100s
I = ?
[tex]\varepsilon = -\frac{\Delta \Phi_{B}}{\Delta t} = IR[/tex]
So the B-field is into the page
[tex]\varepsilon = -\frac{\Delta B l^2}{\Delta t} = IR[/tex]
[tex] -\frac{\Delta B l^2}{\Delta t R} = I[/tex]
Now I have two questions
From this http://answers.yahoo.com/question/index?qid=20090310141926AAQd4oC
The guy took the area from sin(60), I don't understand what he is doing, isn't the area is just l2??
Also, for the direction of the current, is there a quantitative way of knowing the direction?
Judging from [tex] -\frac{\Delta B l^2}{\Delta t R} = I[/tex], the negative sign suggests it is clockwise
Is there another way of knowing the direction?