Boolean Logic | OCR GCSE Computer Science (J277)
Boolean Logic
- 32 questions
- 2 subtopics
- J277/02
- J277/02
Boolean Logic is examined in J277/02, Computational thinking, algorithms and programming.
It covers logic gates and truth tables and Combining gates in logic diagrams.
Sample questions from Boolean Logic
Answer each one closed book first, then open the answer.
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Logic gates and truth tables
What are conjunction, disjunction and negation?
Show the answer
Conjunction is another name for AND, and disjunction is another name for OR. Negation is another name for NOT. -
Logic gates and truth tables
How are the input columns of a three-input truth table filled so that no combination is missed?
Show the answer
The rows count up in binary from 000 to 111. Column A changes every four rows, B every two rows and C every row. -
Combining gates in logic diagrams
What is the output of NOT (A OR B) when A = 0 and B = 0?
Show the answer
The output is 1. A OR B gives 0 because neither input is 1, and NOT 0 gives 1. -
Combining gates in logic diagrams
For P = A AND (B OR C), which rows of the truth table give P = 1?
Show the answer
The rows ABC = 101, 110 and 111 give P = 1. A must be 1 and at least one of B and C must be 1.
The 2 subtopics
One subtopic is one session. Work down the list.
| Subtopic | What it covers | Questions |
|---|---|---|
| Logic gates and truth tables | AND, OR and NOT gates and their symbols, truth tables for up to three inputs, conjunction, disjunction and negation, and gates applied to everyday problems. | 16 |
| Combining gates in logic diagrams | Turning logic diagrams into Boolean expressions and back, worked outputs for combined gates, truth tables for expressions, and designing circuits for alarms and heaters. | 16 |
How the guide is worked
Answering a question from memory stores it far better than reading the answer again. The guide runs that as a fixed procedure on one subtopic at a time, about twenty minutes a session.
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Step 1 · Closed book
Cover the answers. Work through one subtopic and write down what you can. Leave blanks where you have nothing.
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Step 2 · Open book
Go back to the top. Read each printed answer and write it out in full, including the ones you had right.
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Step 3 · Closed book again
Same questions, same order, from memory. The gap between pass one and pass three is the session result.
Read the full method, the return schedule and the research behind it.
Nearby topics
OCR GCSE Computer Science Active Recall Guide
Every topic, not just this one. 740 questions with their answers.