Computer Hardware and Software Questions and Answers

Answer: A

Correct answer: there are a lot more I/O addresses than IRQs.

A PC has hundreds of free I/O addresses but only sixteen interrupt lines, several of them already taken by the keyboard, timer, floppy and disk controllers. Scarcity is what makes IRQ clashes the common case.

Answer: B

Correct answer: + 5 volts

The first Pentium-class processors, the 60 and 66 MHz parts, ran their cores at 5 V. Later Pentiums moved to 3.3 V and lower to keep the power dissipation manageable as the clock rose, which is why the answer depends on which generation is meant.

Answer: A

Correct answer: regular backups

Defragmenting and checking the disk keep it healthy but save nothing when it fails. Only a backup preserves the data through a failure, which is what the question asks about.

Answer: A

Correct answer: 9

On the 16-bit ISA bus the second interrupt controller is cascaded through IRQ2, so a device requesting IRQ2 is actually serviced as IRQ9. The two are the same line seen from either side.

Answer: D

Correct answer: IEEE 1284

IEEE 1284 defines the parallel port, including the bidirectional EPP and ECP modes. RS-232 is the serial standard and CAT 5 a cable specification.

Answer: A

Correct answer: Latin Scripts

Dvorak, Colemak and QWERTY are all arrangements of the same set of Latin letters, differing only in where each letter sits. Other scripts have layouts of their own - JCUKEN for Cyrillic, InScript for Devanagari.

Answer: B

Correct answer: Pixels

Resolution is the number of pixels a display shows, quoted as width by height - 1920 × 1080 for Full HD, 3840 × 2160 for 4K. A pixel is the smallest addressable point of the image. The distractors each measure something else about a monitor, and the set is worth keeping apart. Hertz measures the refresh rate, how many times a second the image is redrawn - 60 Hz is standard and higher rates give smoother motion. Inches measure the screen size, taken diagonally. Bytes measure data, not display. What actually determines sharpness is neither resolution nor size alone but pixel density, in pixels per inch: the same 1920 × 1080 looks crisp on a 15-inch laptop and coarse on a 32-inch monitor. Aspect ratio is the shape, 16:9 being usual, and response time in milliseconds is how quickly a pixel changes, which matters for fast-moving images.

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.

Answer: D

Correct answer: 15

Four bits give \(2^4 = 16\) distinct patterns, running from 0 to 15.

\[1111_2 = 8 + 4 + 2 + 1 = 15\]

Answering 16 counts the patterns rather than naming the largest value.

Answer: C

Correct answer: To supply backup power during a mains failure

An Uninterruptible Power Supply carries a battery that takes over the instant mains power fails, giving time for an orderly shutdown. Most also smooth voltage fluctuations, which protects the equipment from surges and sags.