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Current Electricity — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity1 Mark
Question

In a hydrogen discharge tube it is observed that through a given cross-section 3.13   electrons are moving from right to left and 3.12  protons are moving from left to right. What is the electric current in the discharge tube and what is its direction

(a) 1 mA towards right

(b) 1mA towards left

(c) 2mA towards left

(d) 2mA towards right
✓

Answer

(a) 1 mA towards right

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