The Total solution for NCERT class 6-12
Write the truth table for circuit given in Fig. 14.47below consisting of NOR gates and identify the logic operation (OR, AND, NOT)which this circuit is performing.
(Hint: A = 0, B = 1 then A and B inputs of second NOR gatewill be 0 and hence Y=1. Similarly work out the values of Y for othercombinations of A and B. Compare with the truth table of OR, AND, NOT gates andfind the correct one.)
A and B are the inputs of thegiven circuit. The output of the first NOR gate is. It can be observed from the followingfigure that the inputs of the second NOR gate become the out put of the firstone.
Hence, the output of the combination is given as:
The truth table for this operation is given as:
A
B
Y (=A + B)
0
1
This is the truth table of an OR gate. Hence, this circuitfunctions as an OR gate.