CompTIA A+ Practice Tests. Docter Quentin

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A. An imaging drum is a photosensitive drum that can hold a charge if it’s not exposed to light. It is dark inside an EP printer, except when the laser scanning assembly shines on particular areas of the photosensitive drum.

B. A micro-ATX motherboard is a 9.6″ square. ATX motherboards are 12″ × 9.6″, mini-ITX motherboards are 6.7″ × 6.7″, and pico-ITX motherboards are 3.9″ × 2.8″.

D. Resolution is the number of pixels used to draw a computer screen. Refresh rate determines how many times per second the screen can be redrawn. Frame rate tells you how many frames per second the original content was filmed in. Aspect ratio defines the dimensions (width × height) of an image.

B. In a RAID 5 array, each stripe places data on n– 1 disks, and parity computed from the data is placed on the remaining disk. The parity is interleaved across all the drives in the array so that neighboring stripes have parity on different disks. Said differently, you lose the equivalent of one hard disk worth of storage to hold the parity information.

D. The disable execute bit allows for the CPU to set aside an area of memory and refuse to execute any code placed into that memory location. Oftentimes this serves as a buffer area. The result is that malicious buffer overrun attacks are less likely to succeed.

D. Cloud printing allows for printing to a remote device, one that is not necessarily located on your local network. Essentially, you are using the Internet to send the print job from your device to the printer from which you want the output to come, and the printer can be located practically anywhere in the world.

A. Heat sinks are often made of metal, with many fins on them to increase surface area and dissipate heat faster. Many modern CPU heat sinks will have both a fan (which requires power) and the finned metal heat sink.

A, C. VGA is an analog video connector, and RJ-11 connectors are used with modems. Modems receive a digital signal from the computer but then modulate that signal to analog to transmit over common phone lines.

B. Wi-Fi and Bluetooth can be used to connect a printer temporarily to a single computer (or mobile device), and the connection does not have permanent status. This type of configuration is known as an ad hoc network connection.

A, B. With up-plugging, you can put a smaller PCIe card into a larger slot, even though it does not fill it up completely. For example, you can insert an x8 card into an x16 slot. The x8 card won’t completely fill the slot, but it will work at x8 speeds.

C. RAID 1 is called disk mirroring; it writes data simultaneously to both drives. If one drive fails, the other still has a working copy of the data. RAID 0 is disk striping and does not provide fault tolerance. RAID 5 is striping with parity and provides fault tolerance, but it requires three hard disks.

A. During the cleaning step, a rubber blade inside the toner cartridge scrapes any toner left on the drum into a used toner receptacle, and a fluorescent lamp discharges any remaining charge on the imaging drum. (Remember that the drum, being photosensitive, loses its charge when exposed to light.)

C. Plasma displays place electrodes in front of and behind sealed chambers full of inert gas (such as neon) and vaporized mercury. Current is run through the gas to ionize it and cause it to light up.

B. The audio connector on the front or top panel will use a round, 3.5mm connector. You can plug speakers or headphones into it.

D. With most dual-channel motherboards, RAM will work just fine if one module is installed. However, you will get better performance if you fill the entire bank.