Let E=Eo (err...free space, not sure how to represent the symbols)(adsbygoogle = window.adsbygoogle || []).push({});

V=90z^(4/3) in the region z=0(Potential)

a) Find expressions forE,Dand pv (volume charge density) as functions of z

My work:

E=-div V=0+0)120z^(1/3)az=120z^(1/3)az V/m

D=EoE=1.062z^(1/3)az nC/m^2

pv=div D=.354/z^(2/3) nC/m^3

b)If the velocity of the charge density is given as vx=5x10^6 *z^(2/3) m/s, find Jz (current density) at z=0 and z=.1m

My work:

Now this is where I am confused because J=pv*v(volume charge density*velocity vector). And the book only gives the x component of the velocity vector and asks for the z component of the current density. If you ask me, that means the z component of the current density is 0, but I have no way of checking my answer.

Is this correct?

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# Homework Help: Current Density

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