5 (a) Convert the denary value 178 into an 8-bit binary number - OCR - GCSE Computer Science - Question 5 - 2021 - Paper 1

Transistors are fundamental components in digital circuits that act as switches. They can be in one of two states: on or off, corresponding to binary 1 and 0, respectively.

When a transistor is on, it allows current to flow, representing a binary 1. Conversely, when it is off, no current flows, representing a binary 0.

By combining multiple transistors, complex values can be stored by creating a binary representation of the value where the state of each transistor indicates a specific binary digit.

To convert the binary value 11000111 to hexadecimal, we can group the binary digits into sets of four, starting from the right:

• 1100 0111

Now, we convert each group to its hexadecimal equivalent:

• 1100 = C
• 0111 = 7

Therefore, the hexadecimal representation of the binary number 11000111 is C7.

Azmi's statement is Incorrect.

Justification: While hexadecimal notation can represent values more compactly than binary (using fewer digits), it does not mean it takes up less storage space in total. In a computer's memory, the storage space is typically oriented towards bytes (8 bits), and the size used by hexadecimal values would be determined by the bit representation; thus, the storage space remains the same regardless of whether the format is binary or hexadecimal.

1. Right shift of 2 places on 10101000 → 00101010 (divides by 4)
2. Left shift of 1 place on 00101100 → 01011000 (multiplies by 2)
3. Right shift of 2 places on 11101001 → 00111010 (divides by 4)
4. Left shift of 3 places on 00001111 → 11111000 (multiplies by 8)

To add the two binary numbers 00110110 and 10010110:

  00110110
+ 10010110
-----------
  11001100

The result of the addition is 11001100.