An abstraction of a computer - Answers
Q1.
Hardware device | input device | output device | storage device |
Keyboard | √ | ||
Speakers | √ | ||
Microphone | √ | ||
Pen drive | √ | ||
SD card | √ | ||
Headphones | √ | ||
Graphics tablet | √ | ||
DVD R/W | √ | ||
Concept keyboard | √ | ||
Trackball | √ | ||
Bar code reader | √ | ||
Inkjet printer | √ | ||
QR code reader | √ | ||
Hard drive | √ | ||
Web cam | √ | ||
Mouse | √ | ||
Plotter | √ | ||
Tracker pad | √ | ||
Micro SD card | √ |
Q2. CPU stand for Cetral Processing Unit.
Q3. If you didn't have a storage device in a computer, you'd need to reload all the software everytime you switched on the computer. You also wouldn't have a way of backing up work so would have to do it all again!
Q4. Programs in RAM sometimes start to interfere with each other, causing problems. Switching the power off then on clears out the RAM so that the software can be reloaded again, hopefully in an orderly fashion.
Q5. Sometimes, you can't fit all of a program you are running into RAM. You therefore have to store parts of the program on the hard drive and then get back those parts when you want to use them. The problem is that hard drives are very slow. If you had more RAM, you could fit the whole program in RAM and it would work very quickly.
Q6. Volatile = lose contents when power is switched off (e.g. RAM). Non-volatile = keeps contents when power switched off (e.g. hard drive).
Q7. Cache is superfast RAM. Like RAM, the more cache you have the better.
Q8. Booting-up a computer means powering it on.
Q9. The program in ROM checks that the hardware is working correctly. It carries out a Power On Self Test (POST) and checks the Basic Input Output System (BIOS). It then loads the OS into RAM and hands over control to it.
Q10. Cores are like individual processors in the CPU. A dual core has two. A quad core has 4. The more cores you have, the more jobs a CPU can do at the same time.