Community resourceWorksheet
OCR H446 1.4.3 Boolean algebra exam transition
Part 11 of 11 · H446 1.4.3 · Boolean algebra
This is an assessment piece rather than a teaching one, so it works best as a closed-book check after the rest of the OCR H446 1.4.3 series. Explanatory support is removed, and five examination-style questions run from scenario translation through truth table, named laws and a four-variable Karnaugh map to component comparison.
Students will:
- translate a multi-condition scenario into an expression and a circuit unaided
- complete a truth-table output column in systematic input order
- simplify an expression with named laws and a visible intermediate stage
- annotate the optimal groups on a supplied map and state the simplified result
- compare adder types and explain flip-flop clock behaviour in one extended answer
Inside: 7 explanation cells, 1 fill-in-the-blanks cell and 4 written answers. 23 marks, about 60 to 75 minutes.
Series: H446 1.4.3 · Boolean algebra, part 11 of 11.
Shared by Coding PathwayVerified teacher
- 12 cells
- About 60 minutes
- CC BY-SA 4.0
- Shared 31 Aug 2026
- Updated 3 Sept 2026
Preview
The whole resource, exactly as a class sees it. Answers and marking are held back.
Boolean algebra exam transition
Complete this assessment independently and without checking answers as you go. Use the command words, supplied evidence and context carefully; correctness is held where the platform supports it.
This is an original examination-style assessment. Explanatory scaffolding is deliberately reduced.
Work independently. Show named algebraic stages and annotate Karnaugh groups on paper where instructed.
Question 1: scenario, circuit and expression
A laboratory alarm sounds when movement is detected and the system is armed, or when an emergency test is active. A supervisor override prevents the alarm in either case.
Use M for movement, A for armed, T for emergency test and O for override.
Write the Boolean expression for output S and draw the corresponding logic circuit on paper.
Use OCR notation and label all inputs and the output.
Students type their answer here.
Question 2: truth table
For P = (A ⊕ B) ∧ ¬C, complete the final output column. Use systematic input order.
| A | B | C | P |
|---|---|---|---|
| 0 | 0 | 0 | row 1 output |
| 0 | 0 | 1 | row 2 output |
| 0 | 1 | 0 | row 3 output |
| 0 | 1 | 1 | row 4 output |
| 1 | 0 | 0 | row 5 output |
| 1 | 0 | 1 | row 6 output |
| 1 | 1 | 0 | row 7 output |
| 1 | 1 | 1 | row 8 output |
Question 3: named laws
Simplify ¬(¬A ∧ ¬B). Show the named laws and an intermediate stage.
Apply De Morgan before removing double negations.
Students type their answer here.
Question 4: Karnaugh map
The following map represents a four-input circuit.
| CD / AB | 00 | 01 | 11 | 10 |
|---|---|---|---|---|
| 00 | 1 | 1 | 0 | 0 |
| 01 | 0 | 0 | 0 | 0 |
| 11 | 0 | 1 | 1 | 0 |
| 10 | 1 | 1 | 1 | 0 |
Annotate the two optimal groups on paper and write the simplified Boolean expression.
Check for top-to-bottom wrap-around and useful overlap before finalising.
Students type their answer here.
Question 5: logic components
Describe the difference between a half adder and full adder, then explain the purpose and clock behaviour of a D-type flip-flop.
Make four distinct points.
Students type their answer here.
Final review before hand-in
- Every variable is defined or inherited from the question.
- Gate symbols, not flowchart symbols, are used.
- Brackets show operator scope.
- Named laws have visible intermediate stages.
- Karnaugh groups contain only 1s, use powers of two and show wrap-around.
- Component explanations distinguish input count, state and clock behaviour.