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Current Electricity — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity2 Marks
Question
Electrons are continuously mobile in any conductor but then too, no electric current flows in the conductor till an electric source is joined across its ends. Explain.
✓

Answer

Due to random motion of electrons, the net flow of electron in any definite direction is zero and because of this no current flows in the conductor. On applying potential difference across its ends, an electric field is developed in the conductor and because of this a force acts on the electrons in a direction opposite to the direction of electric field and electrons travel in a definite direction. The current starts flowing in the conductor.

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