Q. In presence of interspace charge, at plate voltage of 200 V, the current is 80 mA. Then the current in mA at 400 V will be
A) $160\sqrt{2}$
B) $2\sqrt{2}$
C) $80/\sqrt{2}$
D) None of these
Explanation
(a) $\frac{I_{2}}{I_{1}} = \left( \frac{V_{2}}{V_{1}} \right)^{3/2}\ or\ \ I_{2} = I_{1}\left( \frac{V_{2}}{V_{2}} \right)^{3/2}$
$= 80\left( \frac{400}{200} \right)^{3/2} = 80 \times 2\sqrt{2} = 160\sqrt{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.