OCR GCSE Computer Science

Boolean logic & truth tables

OCR GCSE Computer Science revision on Boolean logic & truth tables. Aligned to the OCR GCSE Computer Science J277 specification. This bank has 46 practice questions on this topic.

Sample questions (3 of 46)

  1. Question 1

    In Boolean logic, what does A AND B equal when A = 1 and B = 0?

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    Answer: 0

    AND truth table: 0 AND 0 = 0, 0 AND 1 = 0, 1 AND 0 = 0, 1 AND 1 = 1. ONLY when both inputs are 1 does the output go to 1. Think 'must satisfy both conditions'.

  2. Question 2

    What is the result of NOT(0 OR 1)?

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    Answer: 0

    Work the brackets first: 0 OR 1 = 1 (OR is 1 if at least one input is 1). Then NOT inverts: NOT 1 = 0. Result: 0. Brackets always come first in Boolean expressions, like BIDMAS for arithmetic.

  3. Question 3

    OR is 1 (true) when...

    • A) Both inputs are 1
    • B) Both inputs are 0
    • C) At least one input is 1
    • D) Inputs are different
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    Answer: At least one input is 1

    OR truth table: 0 OR 0 = 0, 0 OR 1 = 1, 1 OR 0 = 1, 1 OR 1 = 1. Three out of four cases give 1. Real-world: 'do I take an umbrella if it's raining OR cloudy?' — yes if either condition true.

Want to test yourself on the remaining cards for this topic?

43 more questions on Boolean logic & truth tables — plus mistakes tracking and spaced repetition across the whole Computer Science spec.