Quiz 3

Surge Protector

- protect your computer from power surges through electric lines. Note: You should buy a surge protector that has connections for telephone jacks as power surges can also come through your telephone lines

Monitors:

a. Cathode Ray Tube (CRT)- looks and works much like a color television set b. Liquid Crystal Display (LCD)- Flat screen devices used on laptops and flat displays used for desktop computers.

Expansion Cards

allow you to add hardware components to a computer. The actual circuit cards get attached inside the computer. Some have ports so that peripheral devices can plug into them. An example of an expansion card is a sound card that allows speakers to be plugged into it.

Ports

connections that allow peripheral devices to plug into the back of the computer. Ports don't require you to open the system unit to add hardware to your computer system.

Uninterruptible Power Source (UPS)

is a large battery that is connected to your computer in the case of power failure. It allows you time to save your information before shutting the computer down. You should have the system unit and the monitor plugged in as a minimum.

The primary input device of a computer is...

the Keyboard

Color Depth

the number of different unique colors that can be displayed is known as the color depth. As with resolution, color depth can be adjusted. Typically the lowest number of colors displayed will be 256. Most people tend to choose a larger color depth such as 24-bit color which represents 16.7 million colors.

The Bus

the physical circuit connection between an expansion card and the CPU. The larger the bus the faster the information can be transmitted.

Pointing Devices

used to navigate through a graphical interface found in most of today's computers. The mouse is the most typical example of a pointing device.

Types of Printers:

1 Laser- use laser in combination with static electricity to place an image on a drum, that drum picks up powder toner in those locations. The sheet of paper is placed over the drum and the toner is transferred to the paper. Heater coils then heat/bake powder toner onto sheet. The discharge lamp wipes the image of the drum. The drum then receives the next page image to be duplicated and repeats the process. 2 Inkjet/BubbleJet- sprays liquid ink onto paper like a spray can 3 Dot Matrix- considered an impact printer since the print head actually strikes an ink ribbon into the paper.

Refresh Rate

Refers to how fast the entire screen image can be redrawn on the monitor. This only applies to CRT monitors as LCD monitors don't have a refresh rate. Since this is a measurement of speed it is always shown as a hertz value. Typically a refresh rate of 70 Hertz or higher will produce a good image, anything below this will cause a noticeable screen flicker.

Video Controller Card

The monitor plugs into an expansion card inside the computer that sends video information to the monitor

A pixel is...

a single point of light on a monitor.

Resolution

number of pixels a monitor is displaying. Resolution settings are always shown in the following format Width X Height. An example is 640 X 480 which means there are 640 pixels across and 480 pixels down. The number of pixels that are displayed can be changed by the user. The more pixels on the screen the better the quality of the picture will be. A high resolution (larger number of pixels) will shrink the images on the screen, so it is best to pick a resolution that is easy on the eyes.

Dot Pitch

one of the few things in a computer where a smaller number is better. A dot pitch refers to the distance between pixels on the screen. The smaller the distance between pixels will result in a better quality image on the screen A dot pitch of .24 or lower is good. Anything above a .35 typically produces a fuzzy image on the screen