Backing Storage Devices Learning Intentions for this Unit
Backing Storage Devices
Learning Intentions for this Unit of Work We are learning to: Make comparisons between different backing storage devices using their features. Identify appropriate backing storage devices for a computer system/situation. Perform calculations relating to the storage required for files.
Success Criteria Choose a backing storage devices for a given system or situation and justify my choice. Show all of my working when performing storage calculations.
The Computer System MAIN MEMORY INPUT PROCESSOR WRITE READ BACKING STORAGE OUTPUT
Backing Storage Units 1 bit – the smallest unit of memory 8 bits = 1 byte 1024 bytes = 1 Kilobyte (Kb) 1024 Kb = 1 Megabyte (Mb) 1024 Mb = 1 Gigabyte (Gb) 1024 Gb = 1 Terabyte (Tb) Keep Kilobyte My Garden Megabyte Gigabyte Tidy Terabyte
What are Backing Storage devices? The Main Memory is used to store our work while the computer is on. When the power is switched off this data is wiped. Main Memory Backing Storage devices are used to save our work and programs permanently. Hard Disk with case removed
Terms you need to know ROM – Read Only Memory R – Recordable- Record up to the capacity of the disc RW- Rewritable – Write over many times RE - Recordable Erasable (for Blu Ray) Direct – Data can be written and read in any order Sequential- Data can only be read in the order it was written.
Backing Storage Data Sheet
Backing Storage Questions 1. 2. 3. 4. 5. 6. 7. 8. 9. Name the 3 types of backing storage devices Which type of backing storage devices use a laser to read and write data to it? Which type of backing store has no moving parts? Which backing storage device can hold up to 3 Terabytes of data? Which Solid backing storage devices is a read only backing store? Which backing store only allows you to read the data held on it order? Which backing storage device is commonly used to store High Definition videos? Which Solid backing store is commonly found in smartphones and digital cameras? How many Gigabytes are there in 2 Terabytes? HINT 1 Terabyte = 1024 Gb
Answers 1. 2. 3. 4. 5. 6. 7. 8. Magnetic, Optical and Solid Optical Solid Hard Disk ROM cartridge Digital Audio Tape Blu Ray SD Memory Card
At the computer – www. pcworld. co. uk For each of the backing storage devices find the highest capacity model and note its cost. Cost per Gigabyte = Cost per item/ Capacity found Example: ROM Cartridge: 20. 00 / 8 = £ 2. 50 per Gigabyte Round up to the nearest penny
Calculations 1. 16 bits – What is this in bytes? Remember 8 bits = 1 byte So 16 /8 = 2 bytes 2. 32 bits – What is this in bytes? Remember 8 bits = 1 byte 32/8 = 4 bytes
3. How many bytes in 256 bits? ANSWER: 256 / 8 = 32 bytes 4. How many bytes in 512 bits? ANSWER 512/8 = 64 bytes
5. How many Kilobytes in 2048 bytes ANSWER: 2048 / 1024 = 2 Kb 6. How many Megabytes in 4096 Kilobytes ANSWER: 4096 / 1024 = 4 Mb
5. How many Kilobytes in 2048 bits ANSWER: 2048 / 1024 = 2 Kb 6. How many Megabytes in 4096 Kilobytes ANSWER: 4096 / 1024 = 4 Mb
7. Calculate the storage required for the top 5 downloaded albums shown: Answer in Megabytes ANSWER: 350 + 322 + 258 +289 + 317 = 1536 Mb 8. How many Gigabytes of storage would the 5 albums take up? ANSWER: 1536 /1024 = 1. 5 Gb 9. Which Optical Backing Storage medium will be large enough to hold the 5 albums? ANSWER: DVD Top 5 Downloaded Albums Battle Born 350 Mb The Truth about Love 322 Mb Number 3 258 Mb Coexist 289 Mb Our version of events 317 Mb
10. How many MP 3 s could you fit on a CD-RW (700 Mb) if the average file size was 8 Megabytes? Show all your working Answer: CD-RW Capacity = 800 Mb Ø 700/ 8 = 87. 5 Ø So 87 MP 3 s Ø
Converting between units Question Add 1. 5 Gb to 256 Mb How can we do this if the values numbers above use different units? First we need to covert 1. 5 Gb to Mb. How many Megabytes in a Gigabyte? 1024 Mb So 1. 5 * 1024 = 1536 Mb Now we can add them up 1536 + 256 = 1792 Mb What is this in Gigabytes? 1792 / 1024 = 1. 75 Gb
Show all of your working for the following 1. Add 1 Gb to 512 Mb. Answer in Gigabytes 2. Find the total storage requirements for the following files: MP 3 = 32 Megabytes Alton Towers Trip Photo album = 128 Mb HWB- Health lifestyles video = 2 Gb
Answers 1. 1 Gb = 1024 Mb So 1024 + 512 = 1536 Mb 1536 / 1024 = 1. 5 Gb 2. 2 * 1024 = 2048 So 2048 + 32 +128 = 2208 Mb 2208/1024 = 2. 15625 = 2. 16 Gb to 2 Decimal places
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