IGCSE Computer Science Paper 2 Crossword: 10 Boolean Logic (Modules 562–580)
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Date:
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Crossword
Read each clue and write the matching term in the grid. Numbers in brackets show the letters in each word.
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9
10
Across
- 1. Write the input values on the wires, then work gate by gate from left to right, writing each gate's output on its output wire until you reach the final output X. Word 1 of: _____ a circuit (5)
- 5. A diagram of ______ gates joined by wires. Inputs are on the left, the output is on the right, and each wire carries 0 or 1. A dot where a wire splits is a junction. Word 1 of: _____ circuit (5)
- 7. Mixing up NAND/AND or OR/XOR, rows out of binary order, NOT on the wrong part, missing brackets or columns, wrong input counts, or simplifying a circuit that must be drawn as given. Word 1 of: ______ _____ ________ (6)
- 8. Word 3 of the term in 7 Across: ______ _____ ________ (8)
- 10. A circuit here has at most three inputs (A, B, C) and exactly one ______ X. With 3 inputs the truth table has 8 rows (2 x 2 x 2). Gates with two inputs can be combined to handle the third input. Word 4 of: 3 inputs, 1 ______ (6)
Down
- 2. A circuit, expression and truth table are ______ when each gives the same output X for the same inputs. Check by working out X row by row in each one and comparing the results. (10)
- 3. A dot drawn where wires join, so one input can feed two gates. Wires that cross with no dot are not connected. Draw inputs on the left and the output on the right. Word 1 of: ________ dot (8)
- 4. Follow one ______ of input values through each gate in the circuit, write each gate's output in an extra column, then copy the final value of X into the truth table. Word 3 of: _____ each ___ (3)
- 6. Draw every ______ in the given expression, one for each ______, even if a shorter circuit has the same truth table. Never combine or remove gates. Word 4 of: one ____ per ________ (8)
- 9. Word 2 of the term in 6 Down: one ____ per ________ (4)
Answer Key
IGCSE Computer Science Paper 2 · Modules 562–580
1T
R
A
C
2E
Q
3J
U
4R
U
5L
6O
G
I
C
7C
O
M
M
O
N
P
V
W
C
E
A
T
R
L
8M
I
S
T
A
K
E
S
9G
O
T
N
A
N
10O
U
T
P
U
T
R
E
Across
1TRACE — Write the input values on the wires, then work gate by gate from left to right, writing each gate's output on its output wire until you reach the final output X. Word 1 of: _____ a circuit
5LOGIC — A diagram of ______ gates joined by wires. Inputs are on the left, the output is on the right, and each wire carries 0 or 1. A dot where a wire splits is a junction. Word 1 of: _____ circuit
7COMMON — Mixing up NAND/AND or OR/XOR, rows out of binary order, NOT on the wrong part, missing brackets or columns, wrong input counts, or simplifying a circuit that must be drawn as given. Word 1 of: ______ _____ ________
8MISTAKES — Word 3 of the term in 7 Across: ______ _____ ________
10OUTPUT — A circuit here has at most three inputs (A, B, C) and exactly one ______ X. With 3 inputs the truth table has 8 rows (2 x 2 x 2). Gates with two inputs can be combined to handle the third input. Word 4 of: 3 inputs, 1 ______
Down
2EQUIVALENT — A circuit, expression and truth table are ______ when each gives the same output X for the same inputs. Check by working out X row by row in each one and comparing the results.
3JUNCTION — A dot drawn where wires join, so one input can feed two gates. Wires that cross with no dot are not connected. Draw inputs on the left and the output on the right. Word 1 of: ________ dot
4ROW — Follow one ______ of input values through each gate in the circuit, write each gate's output in an extra column, then copy the final value of X into the truth table. Word 3 of: _____ each ___
6OPERATOR — Draw every ______ in the given expression, one for each ______, even if a shorter circuit has the same truth table. Never combine or remove gates. Word 4 of: one ____ per ________
9GATE — Word 2 of the term in 6 Down: one ____ per ________