| Give three advantages of hardcopy | Permanent
Portable
Easier to make copies |
| Give an advantage for softcopy | Easier to edit( Used for outputs that are continuously changing) |
| Give four advantages of Audio outputs | Suitable for disabled people(blind)
The output is given to many people simultaneously
Attracts the user
User can be far away from the system |
| Give three disadvantages for audio output | Disturbs the enviroment(Not suitable for enviroment such as hospitals and libraries)
Cannot be heard in noisy enviroments
As message is not permanent it has to be repeated |
| What are the two types of printers? | Ink jet printers
Laser printers |
| What are the two types of ink jet printers? | Peizoelectric
Thermal bubble |
| How does a thermal bubble printer work? | Tiny resistors create localised heat which makes ink vaporise , which causes the ink to form a tiny bubble, which expands causing the ink to eject out of the printhead
When the bubble collapses, a vacuum is created causing fresh ink to be drawn into the printhead
The process is repeated until the printing cycle is complete |
| How does a peizoelectric printer work? | A crystal is located at the back of the ink reservoir for each nozzle.
The crystal is given a tiny electric charge which makes it vibrate, which causes ink to be ejected on to the paper.
Simultaneously more ink is brought in
The process is repeated till the printing cycle is complete |
| What are the four main parts of a ink jet printer? | A print head which consists of nozzles which spray ink onto the paper to form characters
An ink jet cartridge for blue, yellow, magenta and black cartridge or single containing all
Stepper motor and belt which moves the print head from side to side across the page
A paper feed which automatically feeds the printer the pages |
| Give three features of the laser printer | Uses dry powder ink
Uses static electricity to produce text and images
Prints the whole at one go |
| Give four differences between ink jet and laser printer | Laser printers use toners , ink jet uses cartridge
Laser printer is faster
Laser printer has better quality
Laser printer is used for larger quantities |
| What is a 3D printer ? | A device which produces three dimensional objects |
| What materials can be used by 3D printer? | Ceramic
Metal
Resin
Wood
Granite |
| What are the advantages of 3D printers ? | Can manufacture products much faster
Products manufactured are cheaper |
| What are the disadvantages of 3D printers? | Violation of copyright leads to unemployment
People will have access to dangerous technologies |
| What is a 2D cutter? | Device used to engrave characters on a flat surface such as nameplates, tombstone, wooden furniture |
| What is a 3D cutter? | Device used to create 3D objects by cutting away material from a block, they are capable of cutting designs inside the object. |
| What are the materials that can be used by the 3D cutter? | Glass
Jade
Metal
Wood
Polymer |
| What are the three type of monitors? | LCD(Liquid Crystal Display)
LED(Light Emitting Diode)
OLED(Organic Light Emitting Diode) |
| How does a LCD work? | Uses a Cold Cathode Flourescent Lamp(CCFL) to emit light onto a grid of liquid crystals |
| What does an LED do? | An LED backlight is used to emit light on the LCD panel |
| What is OLED? | Organic material embedded between metallic rocks which glow when supplied with electricity |
| What is the advantage of LCD? | Cheaper |
| What are the advantages of LED ? | Brighter picture
Less electricity consumption
Shorter time to reach maximum brightness
Longer lifetime |
| What are the advantages of OLED? Give two applications | Less electricity consumption
No backlight(thinner)
Bendable
Mobile phones
Advertising screens |
| What are the advantages of projectors? | Portable
Larger audience
Adjustable screen size |
| What are the disadvantages of projectors? | lower quality than monitors
Time consumed to set up the projector |
| What are the three types of touchscreens ? | Capacitive
Resistive
Infa-red |
| How does capacitive touch screens work? | It contains several layers of glass with electricity flowing between them, when a person touches the screen the electricity in that area passes out of the device through the body
This change is detected by the microprocessor to identify where the screen was touched |
| What are the advantages of capacitive touchscreens? | Cheap
Durable
Visible in bright light
Multitouch |
| What are the disadvantages of capacitive touchscreens? | Only works when touched by hands, stylus and capacitive gloves |
| How does a resistive touchscreen work? | Consists of a polyester sheet below which there is a glass sheet.
When a person touches the screen, the polyester screen touches the glass and the circuit is complete.
When it is complete, the microprocessor can identify where the screen was touched |
| What are the advantages of a resistive touchscreen? | Cheaper
You can use bare fingers, stylus or glove |
| What are the disadvantages of resistive touchscreens? | Not durable
Not multitouch
Not very clear in bright light |
| How does a infra-red touch screen work? | A grid of infrared light sources and sensors are used to detect where the person touches the screen, when the screen is touched the infrared light beam is interupted and the location of the touch can be identified |
| What are the advantages of infrared touchscreens ? | Less affected by scratches on the surface of the device
You can use use it bare finger, gloves and stylus
Multitask is possible |
| What are the disadvantages of Infrared? | Dust particles may produce incorrect touches
Moisture and water will affect the proper working of the screen |
| Where is capacitive touchscreens used? | Mobile phones |
| Where are infrared used? | ATM
Ticketing system
Medical equipment |
