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Current Electricity — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity1 Mark
MCQ
An ionization chamber with parallel conducting plates as anode and cathode has $5 \times 10^7$ electrons and the same number of singly-charged positive ions per $\mathrm{cm}^3$. The electrons are moving at 0.4 m/s. The current density from anode to cathode is $4 \mu \mathrm{A} / \mathrm{m}^2$. The velocity of positive ions moving towards cathode is
  • A
    0.4 m/s
  • B
    16 m/s
  • C
    Zero
  • ✓
    0.1 m/s
✓

Answer

Correct option: D.
0.1 m/s
(d) 0.1 m/s

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