Edexcel GCSE Computer Science (1CP2) Exam Questions

• A Blu-ray Disc (1)
• The only correct answer is A. The correct answer is Blu-ray Disc.
• B is not correct because a CD stores less data than a Blu-ray Disc, up to about 700 MB
• C is not correct because a DVD stores less data than a Blu-ray Disc, up to about 4.7 GB (single-layer) or 8.4 GB (dual-layer)
• D is not correct because magnetic tape is not an optical storage medium

Award up to two marks for a linked description such as:

• Carries out arithmetic operations/calculations, such as addition or subtraction (1) so that the result can be stored in a register (1)
• Carries out logical operations, such as comparing two data items (1) to see which one is greater/larger (1)
• Compares two data items (1) to decide whether a condition is true / which path a program takes next (1)

Allow the result of an arithmetic or logical operation being held/stored in a register, but only where the operation is named.

Do not accept answers that say the ALU stores data or results without naming an operation (registers/main memory store data).

Do not accept answers about controlling components, decoding instructions or timing (that is the control unit or the clock).

Do not award credit for 'it processes data' on its own; an arithmetic or a logical operation must be named.

An example on its own, e.g. 'it adds two numbers', does not earn a second mark; the second mark needs a linked development.

Award up to two marks for a linked explanation such as:

• The instructions/program instructions and data are stored together in main memory/RAM (1) so the CPU can fetch each instruction (from its address) and execute it (1)
• The instructions/program instructions are held in main memory/RAM (1) rather than being built into/part of the hardware, so the computer does not need to be rewired/rebuilt to run a different program (1)
• The next instruction to be executed/instruction is held in main memory/RAM (1) so the CPU can fetch it using its address before it is decoded and executed (1)

For both marks, the expansion must follow/associate with the statement.

A point/statement on its own can only earn one mark.

Do not accept a response that only refers to data being stored in main memory/RAM without referring to the instructions/program instructions.

Do not accept instructions/programs being stored on the hard disk/backing store.

Do not accept 'the program is stored in memory' without saying that it is the instructions/program instructions that are stored there.

Award up to two marks for a linked explanation such as:

• RAM is volatile (memory) (1) because it needs a constant/continuous power supply to hold/store the data it contains (1)
• Data is held in RAM as electrical states/charges (1) so when the power supply is removed these states cannot be kept/refreshed and the data is lost (1)
• RAM is used as short-term storage for the data and instructions currently in use (1) because it can only hold them while the computer has power (1)

For both marks, the expansion must follow/associate with the statement and must link the loss of the data to the power supply being removed.

Accept 'RAM is volatile' on its own for the first mark; the second mark is only awarded for a linked reason about the power supply.

Do not accept 'RAM is temporary/short-term memory' or 'RAM is cleared when the computer is switched off' on its own for both marks, as neither gives a reason.

Do not accept answers that say the data is deleted/cleared/erased by the computer or the operating system, or that the data is saved/moved to secondary storage, without saying why the data cannot be kept (e.g. because RAM needs power/is volatile).