question_answer

Direction for: In each of the following questions a statement of Assertion is given followed by a corresponding statement of Reason just below it. Of the statements mark the correct answer as

Assertion: The logic gate NOT can be built using diode. Reason: The output voltage and the input voltage of the diode have 180° phase difference.

A) If both assertion and reason are true and reason is the correct explanation of assertion.

B) If both assertion and reason are true but reason is not the correct explanation of assertion.

C) If assertion is true but reason is false.

D) If both assertion and reason are false.

Correct Answer: D

Solution :

Key Idea: NOT gate inverts the input signal. The NOT gate has only one input and one output. It combines the in put A with the output 7, from Boolean expression \[\overline{A}=Y\] We cannot realize a NOT gate by using diodes. Instead a transistor has to be used. An electric circuit and truth table for a NOT gate using a n-p-n transistor is shown