Consider a p-n junction diode which has a potential drop of 0.5 V which is to be taken independent of current (under forward bias). If we want to use 1.5 V cell to forward bias the diode then what should be the value of resister (in Ω) used in series with the diode so that current may not exceed 10 mA, and hence may work safely.

The current flow through the resistance in the given circuit is : (Cut-off voltage for both diodes is 0.7 V)

A n-p-n transistor can be used as

The output (X) of the logic circuit shown in figure will be

 

In the above diagram, balance length for E' is ℓ₀. If cross sectional area of wire AB is doubled then what will be new balancing length ?

The figure shows a logic circuit with two inputs A and B and an output C. The voltage wave forms of A, B and C are as given, then logic circuit will be equivalent to :-