Input device — the eleven on the list
An input device is hardware that sends data into a computer system for processing. 0417 names eleven: keyboard, numeric keypad, pointing devices (mouse, trackball, touchpad), remote control, joystick/driving wheel, touch screen, scanner, camera, microphone, sensor and light pen. For each you must know its characteristic (a property), its use (a specific situation) and its advantages/disadvantages (always a comparison).
Five devices are pressed or moved by hand
Keyboard — full set of keys for text, numbers and commands. Numeric keypad — digits 0-9 only, quicker to reach for number entry than hunting across a full keyboard. Pointing device — moved by hand to drive an on-screen pointer in a GUI. Remote control — buttons sending an infrared signal to operate a device from a distance. Joystick/driving wheel — gives continuous, proportional direction and speed rather than fixed steps.
Six devices capture data directly
Touch screen — the screen itself detects the position touched. Scanner — passes light over an existing hard copy to digitise it. Camera — captures a live scene through a lens, and is portable. Microphone — turns sound waves into a digital signal. Sensor — measures a physical quantity continuously and sends it automatically. Light pen — light-sensitive stylus detecting the point on screen, largely superseded by touch screens but still used for CAD.
Drawn from real examiner reports.
Both digitise — that is not a difference
A camera and a scanner both convert something into digital form, so "converts hard copy to digital" is what they have in common and cannot answer a difference question. The credited differences are that the camera is more portable, and that light conditions can affect a digital camera's image, whereas a scanner uses its own controlled light over a fixed original.
Flagged s23 P12 Q3 — candidates repeated the stem wording instead of giving a real difference
A vertical line down the answer space
Ruling the answer space into two columns and listing facts about each device separately blocks the comparison the question wants, so the answer is capped at low marks even when every fact is correct. Write matched sentences instead: the same feature, both devices, one comparative word joining them.
Flagged s23 P12 Q3 — two-column answers were awarded few marks
Invented sensors score nothing
A sensor is named after the physical quantity it actually measures — temperature, light, pressure, moisture. Names improvised to fit the scenario, such as a growth sensor, a pollution sensor or a colour sensor, do not exist and earn no credit. Pick a real sensor and match it to the quantity the scenario says is being monitored.
Flagged w22 P13 Q2 (glasshouse) / s22 P11 Q10a
A thermometer is not a sensor
Asked to name the sensor in a temperature-monitoring system, candidates offered a thermometer, or a motion or light sensor that measures the wrong quantity. Only temperature sensor scores. The answer has to be a sensor, and it has to be the sensor for the quantity named in the scenario.
Flagged w23 P11 Q2d
Sensor output is analogue, not digital
The raw reading a sensor sends is analogue — a continuously varying signal — yet many candidates called it digital. It must pass through an analogue-to-digital converter (ADC) before the computer can process it. Digital data is discrete/binary; analogue is a continuous waveform.
Flagged w23 P11 Q2 / w23 P12 Q2
Sensor advantage with nothing to compare
"The sensor is accurate" is a one-sided benefit and scores nothing. An advantage question about a sensor is asking how it beats a person taking the reading by hand: it reads continuously or far more often than a person could, it is not affected by tiredness or human error, and it works overnight with no staff present.
Flagged w22 P11 Q5a — answers lacked the comparison with the human taking the reading
Naming the gadget, not the input device
Asked which input device a laptop or a smartphone uses, candidates copied "laptop" or "smartphone" straight back — neither is an input device. Name the part that actually captures the data: touch screen, camera, microphone, sensor. The same trap catches every reader question: answer with the device, never with the thing it reads.
A benefit is not an advantage
"It has a large screen" is a benefit and fails; "a larger screen" compares and scores. Every advantage, disadvantage, difference or compare answer needs a comparative word — more portable, quicker, more frequently than — naming what it is being measured against.
Explain means finish with because
A bare comparative is only half an explain answer. State the fact, then start the second half with because: "a camera suits this because it can be carried to the scene, unlike a scanner, which needs a flat surface and an existing original."
Characteristic, use or advantage?
Characteristic = a property: how the device works or what it detects. Use = a specific situation, not "for entering numbers". Advantage = a comparison with an alternative. Giving a use when a characteristic was asked for is the standard way to lose the mark.
Brand names earn nothing
The paper gives no credit for the make or trade name of a camera, a games controller or any other device. Always give the generic device name from the syllabus list.
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