Sampling and Image Resolution Basics

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What is the definition of sample rate?

Number of samples taken per second

Explain what sampling resolution refers to.

Number of bits required per sample

How does the accuracy of a sound file change with respect to sample rates and sampling resolutions?

Increases

Define what image resolution indicates.

Total number of pixels in the X-Y direction of an image Signup and view all the answers

What does colour depth represent in the context of images?

Number of bits to represent each colour Signup and view all the answers

Why does file compression exist?

To reduce file size Signup and view all the answers

What is the purpose of a checksum in data transmission?

To detect errors in the transmitted data Signup and view all the answers

Explain how the checksum is calculated in data transmission.

It is calculated using an agreed algorithm on the block of data being sent. Signup and view all the answers

What happens if the checksum calculated by the receiver does not match the original checksum?

An error is detected and the receiver requests the sender to resend the data. Signup and view all the answers

What is the purpose of an Echo Check in data transmission?

To identify errors by comparing the returned data with the original data. Signup and view all the answers

Which method, between Checksum and Echo Check, involves the sender checking for errors?

Echo Check Signup and view all the answers

In data transmission, what is the action taken if an error is detected by the sender using Echo Check?

The data is re-sent. Signup and view all the answers

How is data stored in a CD/DVD?

Data is stored in pits and lands on the spiral track, and a red laser is used to read and write data. Signup and view all the answers

What technology is used in solid state storage devices like memory sticks/flash memories?

Solid state technology Signup and view all the answers

How are transistors used in storing data on silicon chips?

Transistors are used as floating and control gates to control the flow of electrons and store data. Signup and view all the answers

What is the difference between CDs and DVDs in terms of storage capacity?

DVDs have a larger storage capacity than CDs. Signup and view all the answers

How do optical storage devices like CDs and DVDs read and write data?

They use laser light to read and write data from their surfaces. Signup and view all the answers

What are some uses of memory sticks/flash memories?

They are suitable for transferring files between computers and can be used as small back-up devices for music or photo files. Signup and view all the answers

What is the primary purpose of a firewall?

To help protect computer systems from hacking, malware, phishing, and pharming. Signup and view all the answers

How can one identify a potentially suspicious email based on the sender's email account?

Real organizations usually do not use @gmail accounts for official communication. Signup and view all the answers

What are the two types of firewalls based on their form?

Software and hardware firewalls. Signup and view all the answers

What is the function of a whitelist in the context of firewalls?

To allow access to specific websites or traffic. Signup and view all the answers

Explain the role of a firewall in relation to examining traffic between a user's computer and the public network.

Firewalls analyze the data flow to detect and prevent unauthorized access or malicious activities. Signup and view all the answers

What are some signs that a user can recognize if they are hit with a DDoS attack?

slow network performance, inability to access certain websites, large amounts of spam emails Signup and view all the answers

Define hacking and its potential consequences.

Hacking is the act of illegally gaining access to a computer system without the owner’s permission. It can lead to identity theft, data deletion, corruption, passing on of personal information, or data alteration. Signup and view all the answers

What are some measures that can be taken to prevent hacking?

use of firewalls, setting frequently changed strong passwords, anti-hacking software, intrusion-detection software Signup and view all the answers

Explain what viruses are and how they operate.

Viruses are programs that can copy themselves to delete or corrupt files, causing computer malfunctioning. They need an active host to function. Signup and view all the answers

What is an active host in the context of viruses?

An active host is a functioning software that a virus can affect by either attaching itself to the code or altering the code itself. Signup and view all the answers

How are viruses commonly transmitted to target computers?

Viruses are often sent in forms of email attachments, reside on infected websites, or in infected software programs downloaded on the target user's computer. Signup and view all the answers