Concepts Of Physics MCQ Edition [Volume 2]PhysicsElectric Current through Gases

When a diode exhibits saturated current, its dynamic plate resistance is

Options

Aindeterminate
Binfinity
Czero
Ddifferent for different diodes

Correct answer

B. infinity

Step-by-step solution

The dynamic plate resistance of a diode is defined as the ratio of a small change in plate voltage to the corresponding small change in plate current, given by r_p = V_p I_p . When the diode exhibits saturated current, the plate current becomes constant and independent of the plate voltage. This means that for any change in plate voltage V_p , the change in plate current is zero ( I_p = 0 ). Substituting this into the formula gives r_p = V_p 0 = . Thus, the dynamic plate resistance is infinity.

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