12-62. 12-63. 12-64. 12-65. 12-66. Which of the following is a description of the operation of a drive that uses constant linear velocity? 1. 2. 3. 4. The speed of the disc decreases as the read head moves toward the outer edge of the disc The speed of the disc increases as the read head moves toward the outer edge of the disc The speed of the disc remains constant throughout the range of the read head The physical sizes of the sectors on the spiral track increase toward the outer edge of the disc Sectors on a CD-ROM are accessed by which of the following address forms? 1. Track:sector:head 2. Minute:second:sector 3. Hour:minute:sector 4.  Cylinder:sector When a CD-ROM disc is manufactured, the data is written on the disc in which of the following formats? 1.  Eight-to-fourteen  modulation 2.  Modified  frequency  modulation 3. Run length limited 2, 7 4. Non-return-to-zero The laser used in the optical head of a CD-ROM drive emits light in which of the following bands? 1.  Ultraviolet 2. Visible spectrum 3.  Infrared 4.  White The collimating lens in a CD-ROM drive’s optical head is used to perform which of the following functions? 1. To focus the laser beam on the disc 2. To reduce the divergence of the laser beam 3. To focus the laser beam on the photodector circuit 4. To reduce the intensity of the laser beam 12-67. 12-68. 12-69. 12-70. 12-71. The final step in focusing the laser beam on the disc is accomplished by which of the following items? 1. Optical head 2. Objective lens 3.  Collimating  lens 4. Plastic coating on the disc Splitting the reflected laser beam and directing the split beams to a set of photodiodes is used in which of the following functions? 1. Ensuring the disc is rotating at the proper speed 2.  Maintaining  proper  tracking  and  focus 3. Detecting data on the disc 4. Both 2 and 3 above The control section decodes the eight-to-fourteen data read from a disc using what method, if any? 1. 2. 3. 4. Checking the data for parity errors Using the data to address a ROM for the proper byte Adding the data to a set value to find the proper byte None; the data does not need to be decoded The turntable must rotate so that the data track passes over the optical head at what speed? 1. 1.3 meters per second 2. 1.5 meters per second 3. 1.7 meters per second 4. 1.9 meters per second The interface section provides control for which of the following functions? 1. 2. 3. 4. The transfer of data from the CD-ROM drive to the computer The receipt of data from the computer to be written on the disc Both 1 and 2 above The transfer of data from the disc to the control section of the drive 8 8