hardware Flashcards
1
Q
3D printer
A
- process starts from saved digital file that holds the blueprint of object to be printed
- object is then built by sequentially adding layers of a material (polymer, resin) until object is created
- fan cools each layer
2
Q
microphone
A
- microphone acts as a diaphragm
- the incoming sound wave causes vibration
- causing coil to move past a magnet
- electrical signal is produced
3
Q
laser printer
A
- a laser beam and rotating mirrors are used to draw image of the page on a photosensitive drum
- image converted into electric charge which attracts positively charged toner such that it sticks to the image
- electrostatic charged paper is rolled against drum
- charge pulls toner away from drum and onto paper
- heat applied in the fuser to fuse toner to the paper
- electrical charge is removed from drum and excess toner is collected
4
Q
speakers
A
- takes an electrical signal and translates it into physical vibrations to create sound waves
- electric current in the coil creates an electromagnetic field
- electromagnet is repelled by or attracted to permanent magnet
- causing coil to vibrate
- movement of coil causes cone to vibrate, vibration is transmitted to air in front of the cone
- amount of movement will determine frequency and amplitude of wave
5
Q
components of speaker
A
- cone
- coil of wire
- permanent magnet
- dust cap
6
Q
resistive touch screen
A
- consists of two charged plates
- pressure causes the plates to touch, completing circuit
- point of contact is registered
- coordinates are used to calculate position
7
Q
capacitive touch screen
A
- made from materials that store electric charge
- when touched, charge is transferred to the finger
- sensors at the screen corners detect the changes
- points of contact registered, coordinates are used to calculate position
8
Q
VR headset
A
- video is sent from a computer to the headset using a cable
- two feeds are sent to a LCD
- sometimes 2 screens are used
- lenses are used for focusing and reshaping the image
- most headsets use 60 to 120 frame rate and 110 degree field of view to make it realistic
- uses binaural sounds
9
Q
RAM (random access memory)
A
- volatile (temporary) memory
- data can be altered
- stores data in use
- is read/write
10
Q
ROM (read-only memory)
A
- non volatile memory (permanent)
- data cannot be changed
- stores boot up instructions
- is read only
11
Q
SRAM (static RAM)
A
- no refresh required hence uses less power and faster access time
- more expensive as more transistors
- stores each bit using flip flop (allows previously output value to be stored)
- less storage
- used in cache memory (storage for more frequently used data)
12
Q
DRAM (dynamic RAM)
A
- has to be refreshed hence slower access times and needs higher power
- uses single transistor and capacitor
- stores each bit as a charge
- less expensive as less transistors
- more storage
- used in main memory
13
Q
PROM (programmable ROM)
A
- initially empty
- can be programmed only once after created
- data cannot be erased or deleted
- chip becomes unusable
14
Q
EPROM (electronically programmable ROM)
A
- initially empty
- can be overwritten multiple times
- data can be erased/deleted
- EPROM can be erased using UV light
- must be entirely erased before writing
- chip has to be removed from device for reprogramming
15
Q
EEPROM (electrically erasable programmable ROM)
A
- initially empty
- erased by electrical signal to reprogram
- can update data without removing chip
- does not need to be entirely erased before writing
