(a) What is the effective resistance of the diode when it was forward biased by 0.7 volts? ( Reff =V/I )
(b) What is the effective resistance of the diode when it was reversed biased by 0.7 Volts?

a) Effective resistance when diode was forward biased = 0 Ω

b) Effective resistance when diode was reverse biased = ∞ Ω

Explanation:

Please refer attached characteristic curve for diode.

a) As per the characteristic curve, when the diode was forward biased by 0.7 Volt theoretically infinite current was flowing across the diode.

Hence effective resistance for the diode in forward biased == 0  Ω

b) As per the characteristic curve, when the diode was reversed biased by 0.7 Volt theoretically zero (0 amp) current was flowing across the diode.

Hence effective resistance for the diode in forward biased == ∞ Ω

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