A zener diode of power rating 2W is to be used as a voltage regulator. If the zener diode ha s breakdown of 40V and its has to regulate voltage fluctuated between 6 V and 14 V, the value of R_s for safe operation should be_______   $\Omega .$

 

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 :-