Computer Fundamentals Questions and Answers

Answer: B

The characteristic is diligence.

A computer does not tire or lose concentration, so it can repeat the same operation millions of times with the same care. That freedom from fatigue and boredom is what the textbooks call diligence.

Accuracy is the ability to give correct results, speed is the rate at which it works, and intelligence is something a computer does not have of its own; it only follows instructions. None of these describes tireless repetition.

Answer: C

One nanosecond is \(10^{-9}\) seconds.

The prefix nano means one billionth. The common time prefixes are:

\[ \begin{aligned} 1\ \text{ms} &= 10^{-3}\ \text{s} \\ 1\ \mu\text{s} &= 10^{-6}\ \text{s} \\ 1\ \text{ns} &= 10^{-9}\ \text{s} \\ 1\ \text{ps} &= 10^{-12}\ \text{s} \end{aligned} \]

So \(10^{-3}\) seconds is a millisecond, \(10^{-6}\) seconds a microsecond and \(10^{-12}\) seconds a picosecond. Each step down is a factor of a thousand.

Answer: C

The fastest unit, that is, the smallest interval, is the picosecond.

The four units in order of size:

• millisecond = \(10^{-3}\) s
• microsecond = \(10^{-6}\) s
• nanosecond = \(10^{-9}\) s
• picosecond = \(10^{-12}\) s

A picosecond is a thousandth of a nanosecond. Computer operation speeds are often quoted in these small units, and the smaller the unit an operation is measured in, the faster it is.

Answer: D

The answer is Hybrid computers.

A hybrid computer combines analog and digital parts. The analog part handles continuously varying signals, such as radar returns, very fast, and the digital part provides precise calculation, storage and control. That combination suits real-time control tasks, and the textbook examples of hybrid computers are air traffic control, radar and air defence systems, along with patient monitoring in intensive care.

Microcomputers are personal computers, and minicomputers are mid-sized multi-user machines. Supercomputers are the fastest machines, used for huge numerical jobs such as weather forecasting and nuclear simulation, rather than for this real-time signal work.

Answer: C

1024 × 1024 × 1024 bytes is 1 GB.

Each step up the binary scale multiplies by 1024:

\[ \begin{aligned} 1024\ \text{bytes} &= 1\ \text{KB} \\ 1024\ \text{KB} &= 1\ \text{MB} \\ 1024\ \text{MB} &= 1\ \text{GB} \end{aligned} \]

So \(1024^3 = 2^{30}\) bytes is one gigabyte.

1 KB is only 1024 bytes and 1 MB is \(1024^2\) bytes, so those options stop one or two steps short. 1 TB would need a fourth factor of 1024, that is \(2^{40}\) bytes.

Answer: B

GIGO means errors caused due to incorrect input or unreliable programs.

Garbage In, Garbage Out is the principle that a computer processes exactly what it is given. If the input data is wrong or the program's logic is faulty, the output will be wrong too, however fast or accurate the machine itself is.

Slow processing, lack of storage and outdated software can cause other problems, but they are not what GIGO describes. The term is about the quality of what goes in, not the speed, capacity or age of the system.

Answer: D

Correct answer: EuroNET

EuroNET was the packet-switching network built by the European Community in the late 1970s to link its member states’ research and information services, using the X.25 protocol. Ring, star and LAN describe network shapes and scopes rather than switching techniques.

Answer: B

Correct answer: Driver

A Trojan horse, a virus and a worm are all malicious programs written to damage a system or spread through it. A device driver is legitimate system software that lets the operating system communicate with a piece of hardware.

Answer: C

Correct answer: Rotational delay

Reaching a sector takes two movements: the arm steps to the right track - the seek - and then the platter must turn until the sector passes under the head, which is the rotational delay or latency. On average it is half a revolution, so a 7200 rpm disk averages about \( \tfrac{1}{2} \times \tfrac{60}{7200} = 4.2 \) ms.

Answer: B

Correct answer: ROM

ROM is non-volatile: its contents are fixed when it is manufactured or programmed and survive with the power switched off, which is why the start-up firmware lives there. RAM loses everything when power is removed. VLSI and LSI describe scales of integration, not kinds of memory.