Data Representation J277 Revision

What is the primary function of RAM in a computer system?

• To store data permanently

• To store data temporarily for quick access

• To process data

• To connect to the internet

Answer explanation

The primary function of RAM (Random Access Memory) is to store data temporarily for quick access by the CPU, allowing for faster processing compared to permanent storage options.

Which of the following is an example of secondary storage?

• CPU

• RAM

• Hard Disk Drive (HDD)

• Cache

Answer explanation

A Hard Disk Drive (HDD) is an example of secondary storage, as it stores data persistently. In contrast, CPU, RAM, and Cache are types of primary storage used for processing and temporary data storage.

What is the main characteristic of ROM?

• It is volatile

• It can be written to multiple times

• It is non-volatile

• It is used for processing data

Answer explanation

The main characteristic of ROM (Read-Only Memory) is that it is non-volatile, meaning it retains its data even when the power is turned off. This distinguishes it from volatile memory, which loses data when power is lost.

Which type of storage is typically used for the operating system and applications?

• Primary storage

• Secondary storage

• Tertiary storage

• Cloud storage

Answer explanation

Primary storage, such as RAM, is used for the operating system and applications because it provides fast access to data that the CPU needs to execute tasks. Secondary and tertiary storage are slower and used for data storage.

How is data represented in an image file?

• As text

• As pixels

• As sound waves

• As binary code

Answer explanation

Data in an image file is represented as pixels, which are the smallest units of an image. Each pixel contains color information, allowing the image to be displayed visually. Therefore, the correct answer is 'As pixels'.

What does each pixel in a digital image represent?

• A single colour

• A single sound

• A single character

• A single bit

Answer explanation

In a digital image, each pixel represents a single color. Pixels are the smallest units of an image, and their color values combine to create the overall picture. The other options do not accurately describe what a pixel represents.

What is the purpose of ASCII in computing?

• To encode images

• To encode text characters

• To encode sound

• To encode video

Answer explanation

ASCII (American Standard Code for Information Interchange) is used to encode text characters, allowing computers to represent and manipulate text in a standardized way. It does not encode images, sound, or video.

How many bits are used in standard ASCII encoding?

• 4 bits

• 7 bits

• 8 bits

• 16 bits

Answer explanation

Standard ASCII uses 7 bits to represent characters, allowing for 128 unique symbols. This includes control characters and printable characters, making 7 bits the correct choice.

What is the main advantage of Unicode over ASCII?

• It uses fewer bits

• It can represent more characters

• It is faster to process

• It is easier to understand

Answer explanation

The main advantage of Unicode over ASCII is that it can represent more characters. While ASCII is limited to 128 characters, Unicode supports a vast range of characters from various languages and symbols, making it more versatile.

Which of the following is a valid Unicode character encoding?

• UTF-8

• ASCII-7

• BMP-16

• HEX-32

Answer explanation

UTF-8 is a valid Unicode character encoding that supports all Unicode characters. ASCII-7 is a subset of UTF-8, while BMP-16 and HEX-32 are not standard Unicode encodings. Therefore, the correct answer is UTF-8.