NIMCET 2027 Digital Logic Previous Year Questions (PYQs) – Page 1 of 2

✅ Given Gates:

• I. NAND
• II. NOR

✅ NAND Gate:

The NAND gate is functionally complete. It can be used to construct any logic gate (AND, OR, NOT, etc.) by combining multiple NAND gates.

✅ NOR Gate:

The NOR gate is also functionally complete. It can be used to construct any logic gate (AND, OR, NOT, etc.) by combining NOR gates.

✅ Final Answer:

Both NAND and NOR gates are functionally complete.

Staircase Bulb Switch Logic

Question:
A staircase bulb is controlled by two switches — one at each floor. Each switch can independently turn the bulb ON or OFF, regardless of the other switch's position. What logic gate does this resemble?

✅ Correct Answer: Exclusive OR (XOR) Gate

Explanation:

In XOR logic, the output is ON (1) when inputs are different, and OFF (0) when inputs are the same. Similarly, the bulb glows when the switches are in different states and turns OFF when both are in the same state.

Logic Used: XOR Gate