外部硬件裝置：练习题

• a.An electron beam is scanned across the surface to detect the physical depth of the printed bars
• b.The reader uses magnetic induction to sense the metallic ink used in the black bars
• c.The reader uses a camera to take a high-resolution photo and uses OCR to identify the digits
• d.A laser light is reflected off the barcode, and a sensor measures the intensity of the light reflected back

• a.It uses NAND flash memory and a controller to manage data in pages and blocks
• b.It uses an array of capacitors that must be constantly refreshed to retain data
• c.It uses a read/write head to magnetise small areas on a spinning platter
• d.It uses a laser to burn small pits into a reflective surface to represent bits

• a.Data can only be written to an SSD when it is in a 'low power' state to prevent heat damage
• b.An SSD can write data to a page, but it must erase an entire block before a page within it can be overwritten
• c.Pages can be overwritten individually, but blocks must be erased before being read
• d.An SSD must be formatted every time a single file is deleted to maintain speed

• a.I/O Controller
• b.Graphics Processing Unit (GPU)
• c.Digital-to-Analogue Converter (DAC)
• d.Analogue-to-Digital Converter (ADC)

• a.It uses a larger cache memory which stores the entire contents of the drive
• b.It has no moving parts and does not need to wait for a disk to rotate to the correct sector
• c.It uses a faster serial bus than the magnetic platters used in an HDD
• d.It uses magnetic induction which is inherently faster than electrical charging

先自己写一遍答案，再对照解题步骤。

先自己写一遍答案，再对照解题步骤。

先自己写一遍答案，再对照解题步骤。

先自己写一遍答案，再对照解题步骤。

先自己写一遍答案，再对照解题步骤。