A triode valve has a dynamic plate resistance of 10 k . Determine the change in the plate current when the plate voltage is altered from 200 V to 220 V .

Step-by-step solution

The dynamic plate resistance of a triode valve is given by the ratio of the change in plate voltage to the change in plate current at a constant grid voltage. r_p = V_p I_p Given: r_p = 10 k = 10 10^3 Initial plate voltage, V_ p1 = 200 V Final plate voltage, V_ p2 = 220 V Change in plate voltage, V_p = V_ p2 - V_ p1 = 220 - 200 = 20 V Substituting the values into the formula: I_p = V_p r_p I_p = 20 10 10^3 I_p = 2 10⁻³ A I_p = 2 mA