Computer Hardware and Software Questions and Answers

Answer: A

Correct answer: 200

A person begins to feel a static discharge at around three thousand volts, so 200 V passes entirely unnoticed - while being several times what it takes to damage a chip.

Answer: A

Correct answer: UPS

Only a UPS supplies power through an interruption; a surge protector deals with the opposite problem, and grounding with a third.

Answer: D

Correct answer: Gigahertz

Processor speed is quoted in gigahertz, the number of clock cycles per second - 3 GHz meaning three billion cycles a second. It is a poor measure of performance on its own, and knowing why matters more than knowing the unit. Two processors at the same clock speed can differ greatly because of the number of cores, the instructions completed per cycle, the size of the cache, and the memory bandwidth available. Comparing clock speeds across different architectures is close to meaningless. The distractors measure other things entirely: gigabytes measure storage or memory capacity, megabits per second measure network speed, and dots per inch measure printer or scanner resolution. Modern processors also vary their clock dynamically, running below the nominal speed when idle to save power and boosting above it briefly under load - so the quoted figure is a base rating rather than a constant.

Answer: C

Correct answer: Request to send

RTS is one of the RS-232 handshaking lines: the sender raises it to ask permission to transmit, and the receiver answers with CTS, clear to send.

Answer: C

Correct answer: Toner cartridges

A toner cartridge is designed to be returned, cleaned and refilled, and manufacturers provide the packaging to send it back. Boards, batteries and cathode ray tubes all contain hazardous materials and need specialist treatment.

Answer: B

Correct answer: EMI Electromagnetic Interference

A power cable carries alternating current, which radiates a magnetic field, and that field induces noise in a signal cable running alongside it. Crossing them at right angles, or separating them, is the remedy.

Answer: A

Correct answer: Placing an IC in a non-conductive plastic bag

An ordinary plastic bag is an insulator and generates charge as the component moves inside it - which is why antistatic bags are made conductive. A grounded mat and a touched chassis both drain charge away.

Answer: B

Correct answer: 640 x 480

Standard VGA graphics is 640 by 480 pixels in 16 colours. The higher resolutions belong to SVGA and its successors.

Answer: B

Correct answer: DVD

A DVD is optical storage: data is written as microscopic pits on a reflective layer and read by a laser detecting the change in reflection. CDs and Blu-ray discs work the same way. The three storage technologies are distinguished by how the data is held. Magnetic storage - hard disks, tape - uses the orientation of magnetic domains. Optical storage uses pits read by a laser. Solid-state storage - SSDs, USB flash drives, memory cards - traps charge in floating-gate transistors with no moving parts at all. Optical media have particular strengths: they are cheap to mass-produce by stamping, immune to magnetic fields, and reasonably durable. Their weaknesses are low capacity, slow access and the need for a drive, which is why they have largely disappeared from laptops. RAM is not storage in this sense at all but volatile working memory.

Answer: A

Correct answer: Disconnect the AC power cable

Total protection means no conducting path at all, and only unplugging achieves it. A surge protector clamps a spike but is overwhelmed by a direct strike, and switching off leaves the cable connected.