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)
1