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The picture shows the direction of the magnetic field around a current carrying wire. I wonder what will be the direction of the electric field with respect to the direction of the magnetic field ? I am trying to visualize both electric and magnetic field at the same time. I am getting the picture of the direction of the magnetic field everywhere but could not find any picture that shows both of them togather.

enter image description here.

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In a circuit involving potential drop (so, not purely a current wo/voltage,) the e-field around conductors is perpendicular and radial, and the e-field around resistors is radial with some tilt.

For conductors with arbitrarily small resistance, the flux-lines of e-field appear in the space outside the conductor, and are connecting the surface-charge with charges found upon other, distant parts of the circuit (e.g. parallel wires having opposite charge.) Here's the oversimplified visual version:

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  • Simple circuit:

    SIMPLE CIRCUIT

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  • Magnetic flux, circles around wires
    enter image description here

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  • E-field flux, radial lines connecting surface-charge enter image description here

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  • Both together: cross product is poynting flux, energy-flow from source to sink enter image description here

. Notice that the fields are those of a 2-wire waveguide or transmission line? Exactly right. The same physics applies at Zero Hz DC, and also applies at 60Hz AC, and also at radio frequencies.

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  • $\begingroup$ Thanks alot for your answer. It was really great. Although i am not aware of the poyenting vector but you made many things clear to me. Is this how the electromagnetic waves look like ? they say that in an electromagnetic waves both electric and magnetic fields are perpendicular to each other. and the picture you have shown magnetic and electric field also look perpendicular to eachother. $\endgroup$ – Alex Jun 13 '18 at 10:52
  • $\begingroup$ as the electromagnetic waves are produced by the acceleration of the charges. $\endgroup$ – Alex Jun 13 '18 at 10:54
  • $\begingroup$ Yes, DC circuits employ electromagnetic waves. But the "wave" is just one large hump, many hours wide. This is little different than 60Hz power lines, where each hump is 8.33mS wide. The fields during the middle of each hump, they look like the diagram above. Two-wire waveguides function independent of frequency, and can transmit energy at zero Hz or at 50 GHz, or anything between. PS in the above, if the wires are resistive, then the e-field isn't at right angles to the wires. It tilts slightly, as EM energy from space is moving radially inwards to the wires, becoming heat in metal. $\endgroup$ – wbeaty Jun 13 '18 at 21:29
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Electric field lines describe the force experienced by positive point charge at a point. In a current carrying wire,the force experienced by a positive point charge is in the direction of current,so electric field is in the direction of current.But outside a current carrying wire there won't be any field lines as there is no electric force .

Electric field was produced inside the wire due to the potential difference created by the battery.But outside the wire there is no such thing.

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The current flows in the direction of the electric field. Since the current is the direction of positive charge flow and the electric field is defined by the direction a positive charge would move, the two are the same thing.

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