Menu

Edexcel GCSE Computer Science (1CP2) Exam Questions

Build a practice paper from 693 exam-style questions, each with its mark scheme and example answers. Print it, or answer it on paper and then open the mark schemes. Or browse the questions by topic.

Build a paper

Topics (none ticked: all of them)
Question types (none ticked: all of them)

Practice paper

3 questions · 6 marks

Pick again
Print
1Describe2 marksWired Connections Swap Remove

A farm uses wired connections to link sensors in its fields to a computer in the farmhouse.

Describe how the range of a wired connection can affect the performance of this network.

[2 marks]
Mark scheme

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

  • (Twisted pair/copper) cable only carries data over a limited distance (about 100 metres) (1) so sensors further away need another switch/device to pass the data on to the farmhouse (1)
  • Fibre optic cable can carry data over much longer distances (1) so wired connections can reach sensors across the whole farm (1)
  • Data sent further than the cable's range is not received (1) so the computer in the farmhouse does not get readings from those sensors (1)
  • A wireless connection can reach sensors that are out of range of the cables (1) so a mix of the two can give readings across the whole site (1)

Allow responses about signal weakening/being lost over a long cable.

Do not accept responses about bandwidth or speed, as range is about distance, not the amount or rate of data.

Example answers and how they were marked
Full marks2/2

Twisted pair copper cable only carries data for about 100 metres so a switch is needed in each field to pass the readings on to the farmhouse.

Why: Point that copper cable has a limited distance (1) linked to needing another device to extend the network (1).

Some marks1/2

Fibre optic cable can carry data much further than copper cable.

Why: Gives the first point of a linked pair (1) but does not develop it to say what this allows the farm to do.

No marks0/2

A longer cable gives the network a bigger bandwidth so the sensors work faster.

Why: About bandwidth and speed rather than range, which the mark scheme says is not accepted.

2Explain2 marksTopologies Swap Remove

A bus topology has a terminator at each end of its cable.

Explain why terminators are needed in a bus topology.

[2 marks]
Mark scheme

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

  • Terminators absorb the signal at the ends of the cable (1) so it is not reflected back along the bus (1)
  • Terminators prevent signals reflecting/bouncing back (1) so the reflected signal does not corrupt data on the cable (1)
  • Terminators absorb the signal (1) so it does not collide/interfere with data being sent by other devices (1)
  • Terminators stop the signal reflecting back down the cable (1) so data can be transmitted and received without errors (1)

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

Allow 'interfere'/'corrupt' only where the answer says the reflected signal mixes with/collides with data on the cable.

Do not accept 'to stop the signal' on its own, as stopping the signal is not the same as stopping it reflecting back along the cable.

Do not accept 'to terminate the cable/network', 'to end the cable' or 'to stop the cable breaking'.

Do not award responses that only repeat the stem, e.g. 'because there is a terminator at each end'.

Example answers and how they were marked
Full marks2/2

Terminators absorb the signal at each end of the cable so that it does not reflect back along the bus.

Why: Linked point (1) and reason (1): absorbing the signal is linked to it not being reflected back along the bus.

Some marks1/2

Terminators absorb the signal at the ends of the cable.

Why: Awarded 1 mark for the point that the signal is absorbed, but no linked consequence is given.

No marks0/2

They terminate the network so the cable does not break.

Why: No credit: it does not say the signal is absorbed or that reflections are prevented, and the mark scheme rejects 'to terminate the network' and 'to stop the cable breaking'.

3Explain2 marksAddressing Swap Remove

Routers forward data across the internet.

Explain how a router uses the destination IP address of a packet to send the packet towards its destination.

[2 marks]
Mark scheme

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

  • The router reads/checks the destination (IP) address in the packet (1) so it can forward/send the packet towards that address/destination (1)
  • The router looks up/compares the destination (IP) address (1) to choose the route/next network/next router for the packet (1)
  • The router uses the destination (IP) address to choose/select the outgoing connection/network (1) so the packet is sent one step closer to its destination (1)

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

Do not accept a restatement of the question, such as 'the router uses the IP address to forward the packet', without saying how the address is used, e.g. checking the destination address or choosing the route/next network.

Do not accept answers that say the router gives/adds an IP address to the packet, or that the router uses a MAC address instead of the destination IP address.

Example answers and how they were marked
Full marks2/2

The router checks the destination IP address in the packet and sends the packet out on the route/network that leads towards that address.

Why: Point (1): the router checks the destination IP address; linked reason (1): this is used to send the packet towards that destination.

Some marks1/2

The router checks the destination IP address in the packet.

Why: Point (1): the router checks the destination IP address; no linked reason is given, so only the first mark.

No marks0/2

It adds an IP address to the packet so the packet knows where to go.

Why: Misconception: the router does not add an IP address to the packet; the mark scheme says not to accept this, so no marks.

Questions by topic

More ways to revise Edexcel GCSE Computer Science (1CP2)

Teachers: build a paper, print it with the mark schemes at the end, and sign your school up to set your classes activities on every topic.

Fetch Decode Explain isn't affiliated with or endorsed by Pearson Edexcel.