T The question is about the concept of the operational amplifier in electronics. For an ideal op. amp., it is said that the input impedance is infiinite and the current allowed by the op.amp. through its input terminal zero or in the case of a practical op.amp., it is nearly zero or negligibly small. It means all the current arriving at the input terminal passes through the outer path containing the feedback resistor R_f. The normal questions a student asks is -"When that is the case, what is the need of the circuit elements at all since all the current flows through only a path outside the op.amp. device? What is the exact role played by several resistors and diodes that are making up the circuit diagram of the op.amp.? How does an enlarged output appear without taking any input?" Is it possible to give a simple, understandable and convincing explanation to a student of higher secondary classes without iindulging in any jargons of advanced and brain teasing explanations using higher electronic terminolgy, for the above questions? I myself find difficult to comprehend the above phenomenon. No reference books in electronics deal with such basic notions and doubts arising in the minds of an average reader as they straight away start analysing everything mathematically.