Question

To get output zero for the following circuit, the correct choice for the input is

a. \(A=1,B=1,C=0\)
b. \(A=0,B=1,C=0\)
c. \(A=1,B=1,C=1\)
d. \(A=1,B=0,C=1\)

• A. a and b
• B. c and d
• C. a and c
• D. b and d

Hint:

The output is Y = (A OR B) AND C; evaluate it for each listed input set.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept
From the circuit, inputs A and B go into an OR gate. Its output and input C go into an AND gate, so \(Y=(A+B)\cdot C\).

Step 2: Evaluate each case
a: \(A=1,B=1,C=0\): \(Y=(1)\cdot 0=0\).
b: \(A=0,B=1,C=0\): \(Y=(1)\cdot 0=0\).
c: \(A=1,B=1,C=1\): \(Y=1\cdot 1=1\).
d: \(A=1,B=0,C=1\): \(Y=1\cdot 1=1\).

Step 3: Select
The output is zero for a and b.

Final Answer:
Inputs a and b give zero output. \[ \boxed{\text{(A) }\text{a and b}} \]