5.3.5 Practice Questions Optical Media
A red laser causes a crystal to form which creates the reflective and non-reflective areas on the bottom of the disc.
Digital Versatile Disc (DVD)
Single-sided discs can hold about 4.7 GB of data. Dual-layer discs can hold up to 8.5 GB of data.
Digital Versatile Disc (DVD)
You have a CD-RW drive that advertises speeds of 32x/12x/48x. What is the read speed of the drive?
48x Explanation The read speed is 48x. When multiple numbers are listed together, the first number is the record speed, the second number is the rewrite speed, and the last number is the read speed. If the drive does not perform rewrite functions, the middle number will be omitted.
Uses blue laser light which has a shorter wavelength, which allows data to be packed more tightly on the disc.
Blu-ray Disc (BD)
Was originally developed for high definition video (expanded content on movie discs), but can also be used for data storage.
Blu-ray Disc (BD)
Explanation
Compact Discs (CDs) were first developed store digital music. Later, the CD technology was adapted to store digital computer data. Data is stored on a CD's disc surface in a series of lands and pits. Reflective light is used to interpret the data on the disc. Digital Versatile Disc (DVD) is an optical media standard that can be used to store large amounts of different types of data ( computer, data, video, audio). Single-sided discs can hold about 4.7 GB of data. Dual-layer discs can hold up to 8.5 GB of data. A red laser causes a crystal to form which creates the reflective and non-reflective areas on the bottom of the DVD-RW disc. Blu-ray Disc (BD) was originally developed for high definition video (and expanded content on movie discs), but can also be used for data storage. Blu-ray uses a blue laser instead of the red laser used with CDs and DVDs. The blue laser light has a shorter wavelength, which allows data to be packed more tightly on the disc.
Disc surface made up of lands and pits. Reflective light used to interpret the data.
Compact Disc (CD)
First developed to store digital music. Later, was adapted to store digital computer data.
Compact Disc (CD)
Which of the following are optical storage devices?
BD CD DVD Explanation Optical storage devices use lasers for both reading and writing information. The following are all optical storage devices: CD (Compact Disc) DVD (Digital Video Disc or Digital Versatile Disc) BD (Blu-ray Disc) HDDS (Hard Disk Drives) are magnetic storage devices. A flash device stores information using programmable, non-volatile flash memory. USB flash drive, SSDs (Solid state Drives), and SDHC memory cards are flash devices.
Which Blu-ray standard defines rewritable disks?
BD-RE Explanation BD-RE is the Blu-ray standard which defines rewritable disks. BD-ROM is the read-only standard and BD-R is the recordable standard. R/RW is used to designate rewritable CD and DVD discs, not Blu-ray discs.
Which optical media has the greatest storage capacity?
Single-layer, single-sided Blu-ray disc. Explanation A Blu-ray disc has the greatest storage capacity of optical media. A single-sided Blu-ray disc holds up to 25 GB of data. Dual-layer or double-sided discs double the storage capacity. Experimental 20 layer Blu-ray discs hold up to 500 GB. Single-layer, single-sided DVDs hold about 4.7 GB. A dual-layer or double-sided DVD can hold up to 8.5 GB; a dual-layer, double-sided DVD can hold up to 17 GB.
