#### transgalactic

##### Banned

here is a question:

http://i25.tinypic.com/8xlcfl.gif

there is endless wire uniformly charged [latex]\lambda=2*10^{-4}C/m[/latex]

and close to it located a wire with [latex]l=0.12_m[/latex]

which has 30 degree angle between him and the endless wire,and it charged in uniformed way so that the total charge on it is [latex]q=3*10^{-9}[/latex]

the distance of the finite wire and the infinite wire is 0.08 meters

A.find the total force acted on the finite wire.

B.find it when [latex]\alpha=0 [/latex]degrees and when [latex]\alpha=90 [/latex]degrees.

gaus law for infinite wire i presume its length is l and distance r.

[latex]E2\pi r h=\frac{q}{\epsilon_0}\\[/latex]

[latex]E=\frac{q}{\epsilon_0 2\pi r h}=\frac{\lambda h}{\epsilon_0 2\pi r h}=\frac{\lambda }{\epsilon_0 2\pi r }\\[/latex]

[latex]\frac{q_2}{l_2}=\lambda_2\\[/latex]

[latex]l_0=l_2\cos \alpha\\[/latex]

[latex]\int_{0}^{l_0}Edl=\int_{0}^{l_0}\frac{\lambda }{\epsilon_0 2\pi r }dl[/latex]

i sum along the finite wire

but the ditance from the infinite changes too.

so it should be a double integral

but its not a 2d body

??

http://i25.tinypic.com/8xlcfl.gif

there is endless wire uniformly charged [latex]\lambda=2*10^{-4}C/m[/latex]

and close to it located a wire with [latex]l=0.12_m[/latex]

which has 30 degree angle between him and the endless wire,and it charged in uniformed way so that the total charge on it is [latex]q=3*10^{-9}[/latex]

the distance of the finite wire and the infinite wire is 0.08 meters

A.find the total force acted on the finite wire.

B.find it when [latex]\alpha=0 [/latex]degrees and when [latex]\alpha=90 [/latex]degrees.

gaus law for infinite wire i presume its length is l and distance r.

[latex]E2\pi r h=\frac{q}{\epsilon_0}\\[/latex]

[latex]E=\frac{q}{\epsilon_0 2\pi r h}=\frac{\lambda h}{\epsilon_0 2\pi r h}=\frac{\lambda }{\epsilon_0 2\pi r }\\[/latex]

[latex]\frac{q_2}{l_2}=\lambda_2\\[/latex]

[latex]l_0=l_2\cos \alpha\\[/latex]

[latex]\int_{0}^{l_0}Edl=\int_{0}^{l_0}\frac{\lambda }{\epsilon_0 2\pi r }dl[/latex]

i sum along the finite wire

but the ditance from the infinite changes too.

so it should be a double integral

but its not a 2d body

??

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