Key relationship
OR=A∨B; AND=A∧B; NOT=¬A; NAND=¬(A∧B); NOR=¬(A∨B).
Physics · Class 12
Logic gates and truth tables
A truth table defines output for every input combination. Inverting gates reverse a basic logical operation. Checking every row avoids confusing OR with AND or NAND with NOR.
Open the interactive experiment →Logic gates and truth tables
உண்மை அட்டவணை ஒவ்வொரு உள்ளீட்டு சேர்க்கைக்கும் வெளியீட்டை அளிக்கும். NOT ஒரு உள்ளீட்டை மட்டும் எதிர்மாற்றும்.
Key notes, relationships and model limits
Remember
A truth table defines output for every input combination. Inverting gates reverse a basic logical operation. Checking every row avoids confusing OR with AND or NAND with NOR.
Common trap
NOT is a one-input operation even when the interface displays an unused B control.
Model limits
Ideal binary inputs and outputs; propagation delays and analog voltage thresholds omitted. NOT ignores input B.
What you will learn
Evaluate gates and interpret complete truth tables.
Try the experiment
Try both scenarios, change one control, and predict the result before checking the graph and readouts.
Think of it this way
Change one input while keeping the others fixed, as you would in a controlled experiment.
Worked example
OR(1,0)=1, AND(1,0)=0, NOR(0,0)=1.
Why this matters
The model connects logic gates and truth tables with an observable reading. Check the equation and assumptions before applying it.
Before you start
SI units · algebra · graph reading
Check your understanding
For NAND with both inputs1, output is?
- 1
- 0
- Undefined
Read the explanation
AND gives1; NAND inverts it to0.
Course connection: Class XII Chapter 14. Consult the roadmap for CBSE, NEET, JEE Main and Advanced scope.