OCR J277 GCSE COMPUTER
SCIENCE PAPER 1. QUESTIONS AND
CORRECT ANSWERS
State what is meant by character set. - ans-
ws ws ws ws ws ws ws ws
All the different characters a computer can represent.
ws ws ws ws ws ws ws
Identify how many different characters that ASCII can represent. - ans-
ws ws ws ws ws ws ws ws ws ws
256 because it has 8 bits per character - 2^8 = 256
ws ws ws ws ws ws ws ws ws ws ws
How to calculate file size - ans-number of bytes/1000 = file size in kilobytes
ws ws ws ws ws ws ws ws ws ws ws ws ws
Calculate the file size of a text file with 2000 characters - ans-
ws ws ws ws ws ws ws ws ws ws ws ws
1 character is 1 byte. 2000/1000 = 2 Kilobytes
ws ws ws ws ws ws ws ws
Identify registers. - ans-MAR, MDR, PC, AC
ws ws ws ws ws ws
PC (Program Counter) - ans-
ws ws ws ws
Stores the address of the next instruction to be fetched from memory. Increments in
ws ws ws ws ws ws ws ws ws ws ws ws ws w
each fetch-execute cycle.
s ws ws
CU (Control Unit) - ans-Controls the flow of data and carries out instructions.
ws ws ws ws ws ws ws ws ws ws ws ws
MAR (Memory Address Register) - ans-
ws ws ws ws ws
Stored the address of the data to be fetched from, or the address where the data is
ws ws ws ws ws ws ws ws ws ws ws ws ws ws ws ws w
to be stored.
s ws ws
ALU (Arithmetic Logic Unit) - ans-
ws ws ws ws ws
Performs the mathematical and logical calculations.
ws ws ws ws ws
Define an embedded system - ans-
ws ws ws ws ws
They are small systems inside a machine that carry out functions specific to the ma
ws ws ws ws ws ws ws ws ws ws ws ws ws ws
chine. Embedded systems have limited functions. They are often built into larger ma
ws ws ws ws ws ws ws ws ws ws ws ws
chines.
True or False: Each colour has a unique binary code. - ans-True
ws ws ws ws ws ws ws ws ws ws ws
True or False: Metadata stores the colour of each pixel in the image - ans-False
ws ws ws ws ws ws ws ws ws ws ws ws ws ws
SCIENCE PAPER 1. QUESTIONS AND
CORRECT ANSWERS
State what is meant by character set. - ans-
ws ws ws ws ws ws ws ws
All the different characters a computer can represent.
ws ws ws ws ws ws ws
Identify how many different characters that ASCII can represent. - ans-
ws ws ws ws ws ws ws ws ws ws
256 because it has 8 bits per character - 2^8 = 256
ws ws ws ws ws ws ws ws ws ws ws
How to calculate file size - ans-number of bytes/1000 = file size in kilobytes
ws ws ws ws ws ws ws ws ws ws ws ws ws
Calculate the file size of a text file with 2000 characters - ans-
ws ws ws ws ws ws ws ws ws ws ws ws
1 character is 1 byte. 2000/1000 = 2 Kilobytes
ws ws ws ws ws ws ws ws
Identify registers. - ans-MAR, MDR, PC, AC
ws ws ws ws ws ws
PC (Program Counter) - ans-
ws ws ws ws
Stores the address of the next instruction to be fetched from memory. Increments in
ws ws ws ws ws ws ws ws ws ws ws ws ws w
each fetch-execute cycle.
s ws ws
CU (Control Unit) - ans-Controls the flow of data and carries out instructions.
ws ws ws ws ws ws ws ws ws ws ws ws
MAR (Memory Address Register) - ans-
ws ws ws ws ws
Stored the address of the data to be fetched from, or the address where the data is
ws ws ws ws ws ws ws ws ws ws ws ws ws ws ws ws w
to be stored.
s ws ws
ALU (Arithmetic Logic Unit) - ans-
ws ws ws ws ws
Performs the mathematical and logical calculations.
ws ws ws ws ws
Define an embedded system - ans-
ws ws ws ws ws
They are small systems inside a machine that carry out functions specific to the ma
ws ws ws ws ws ws ws ws ws ws ws ws ws ws
chine. Embedded systems have limited functions. They are often built into larger ma
ws ws ws ws ws ws ws ws ws ws ws ws
chines.
True or False: Each colour has a unique binary code. - ans-True
ws ws ws ws ws ws ws ws ws ws ws
True or False: Metadata stores the colour of each pixel in the image - ans-False
ws ws ws ws ws ws ws ws ws ws ws ws ws ws
