Chapter2

Question 1

What are the functions of the computers?

Answer 1

1) processing (CPU)

2) storage (HD, USB, CD, DVD, Blueray, SSD, SD-Card)

3) Output devices (Printer, Speaker, Monitor, Projector, Headphones, TV Screen, Projector, Tactile devices, Braille display ”send data out of the computer”)

4) communication devices (Modem, Network card, Bluetooth, WI-FI Card)

5) input devices (keyboard, graphics tablet, microphone, webcam, touchscreen, scanner, mouse, ocr reader “enters data & instructions”)

Question 2

How can you convert from decimal to binary?

Answer 2

Keep dividing the number by two removing any fraction on the odd numbers plate a 1 and the even numbers place a 0 until you reach 1 this will be your binary number writing it from down to up starting from the 1

Question 3

How can you convert from binary to decimal?

Answer 3

You get the number and put it on the 8 weight scale and see its value in the 2^N (1,2,4,8,16,32,64,128)and add there totals

Question 4

How do you represent texts?

Answer 4

1) using ASCII characters (each character has 8-bit code, 256 unique codes for 26 letters, 10 digits, special characters)

2) Unicode (supports more than 100,000 unique characters, uses 32 bits, includes Chinese, Arabic, Japanese characters)

Question 5

What is meant by digitization?

Answer 5

Representation of audio, video, & photos using binary system devices used in such a thing are called analogue-to-digital convertors (ADC)

Question 6

What is the binary system?

Answer 6

The system used to store, process & exchange data in computers, having two symbols 1 & 0

Question 7

What is a Bit?

Answer 7

A binary digit, Its the smallest unit of information a computer can process of value 0 or 1

Question 8

Why is the binary system used in computers?

Answer 8

It is more suitable as it is easy to store by the use of electricity, easy to process having operations of 2 values, easy to read as there is only two values, it is a easy way to represent numbers, text, instructions, photos, videos, etc

Question 9

1 byte is equal to how many bits?

Answer 9

8

Question 10

How many values a byte can represent?

Answer 10

256

2^N

Question 11

A kilobyte is how many bytes?

Answer 11

1KB = 1000 Bytes

Question 12

A megabyte is how many bytes?

Answer 12

1MB = 1million bytes = 1000KB

Question 13

A GIGABYTE is how many bytes?

Answer 13

1GB = 1000 MB = 1 Billion bytes

Question 14

A Tera byte is how many bytes?

Answer 14

1TB = 1000GB = 1 TRILLION BYTES

Question 15

A Petabyte is how many bytes?

Answer 15

1PB = 1000 TB = 1 Quadrillion bytes

Question 16

How is data transfer measure?

Answer 16

In bits

Question 17

What are the computer components?

Answer 17

1) microprocessors, CPU (central processing unit)

2) storage (RAM/ROM)

3) connectivity

Question 18

What is meant by green computing?

Answer 18

It is the use of computers and related resources in an environmentally responsible manner, you can:

1) use e-Resources instead of printing

2) use energy saving devices

3) recycle electronic waste

4) turn off the devices when not in use

Question 19

What are the future trends in computers?

Answer 19

1) Robot servant

2) commuter robot

3) Iot smart cities

4) virtual screens

5) OLED Display (transparent screen)

6) flying cars

7) bendable smartphones

Question 20

What is a CPU?

Answer 20

Central processing unit, an electronic chip that carries out the instructions of computer programming located on the mother board performing:

1) Arithmetical (+, *) 7 logical operations (<, =) “ALU”

2) Input/Output operations of the system (control)

It has several performances:

1) clock speed, measure in Hertz where 1 GHz = 1 billion clock cycles per second

2) world size with its natural unit being 32bits in older pc, 664bits in new pc, embedded systems uses 8 & 16 bits

There is single core cpu, multi core cpu which is multiple cpu on a single chip performing parallel processing, contains cache memory which is an internal storage of data in CPU

CPU must have certain compatibilities:

1) Software compatibilities (all softwares must be compatible with every CPU)

2) backward compatibility (newer cpu versions should be able to run apps designed for older versions)

Question 21

What are the types of memory in a computer?

Answer 21

1) Random access memory (RAM)

2) Read only memory (ROM)

3) flash memory

4) Hard drives (permanent storage)

5) cloud storage

Question 22

What is a random access memory (RAM)?

Answer 22

1) Primary to rate of memory

2) temporary storage for programs and data

It has certain features:

1) Unique address

2) data can be stored and retrieved randomly

3) very fast access (in nanoseconds)

4) data is erased if the power goes off (volatile)

Question 23

What is read only memory (ROM)?

Answer 23

1) it contains:

1) startup information (booting)

2) critical data

Features:

1) cannot write new information

2) cannot be erased (etched on the computer)

Question 24

What can a flash memory do?

Answer 24

It can read/write/erase data, it is non-volatile (data don’t get erased when the power is switched off)

Question 25

What is a hard drive?

Answer 25

It is a primary device used for permanent storage, it is a secondary storage, store programs & data, it is slower than main memory, huge storage capacity there is two types: 1) internal 2) portable

Question 26

What is the memory speed and storage capacity of the different storage devices?

Answer 26

Fastest is CPU (Hz), L1 cache (KB), L2 cache (KB, MB), L3 cache (MB), RAM (GB), HDD (GB, TB) and their storage capacity is from the last to first.

Question 27

What are the types of cloud storages?

Answer 27

1) Dropbox

2) OneDrive

3) iCloud

4) Google Drive

Question 28

What are the features of cloud storages?

Answer 28

1) easy access (you can access it anywhere as long as you have internet connection)

2) huge storage capacities

3) online backup