Digital Electronics & Logic Gates Challenge
25 NEET-standard questions on analog and digital signals, the logic gates OR, AND, NOT, NAND and NOR, truth tables, universal gates, De Morgan’s laws and gate circuits. Answer each one. If you get it wrong, Vidya Ma’am explains it with an animated movie you can control: switch the inputs between 0 and 1 and watch the gate output and the truth-table row light up. Then try again.
NEET UG 2026 syllabus · not in the 2026-27 NCERT textKeys: A–D or 1–4 to answer
🧠 Formula memory tricks (open before you start)
Gate symbolsOR: Y = A + B · AND: Y = A·B · NOT: Y = A′plus = OR, dot = AND, bar = NOT
NAND and NORNAND: Y = (A·B)′ · NOR: Y = (A+B)′NAND = 0 only for 1 1. NOR = 1 only for 0 0
Truth table sizen inputs → 2ⁿ rows2 inputs: 4 rows. 3 inputs: 8 rows
De Morgan(A·B)′ = A′ + B′ · (A+B)′ = A′·B′break the bar, change the sign
Universal gatesNAND or NOR alone can build NOT, AND and OR.NOT: join the inputs. OR from NAND: 3 gates. AND from NOR: 3 gates
Bubbled gatesOR with bubbled inputs = NAND. AND with bubbled inputs = NOR.
Logic levelsLogic 0 = LOW (about 0 V). Logic 1 = HIGH (about +5 V).analog = smooth, digital = two levels
right first tryfixed after explanationstill to fix
Made for NEET students · Progress is saved in this browser · SAMPLE build: voice recording pending