Q10 of 49 Page 352

A plate current of 10 mA is obtained when 60 volts are applied across a diode tube. Assuming the Langmuir-Child equation to hold, find the dynamic resistance rp in this operating condition.

Given,


where ip is the plate current and Vp is the plate voltage


V= 60 volts


I =10 mA


(1) (k is a constant)


Taking derivative on both sides with respect to ip


(2)


Dividing (2)/(1)




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