Test: Computer Hardware - 2 - SSC CGL MCQ

Magnetic Ink Character Recognition (MICR) is a technology commonly utilized in banks to process checks by identifying the magnetic numbers at the bottom. MICR detects characters by analyzing their shapes in a grid and then sends this data to the computer. The characters on checks are printed with a special ink containing iron oxide, which can be magnetized for detection and processing.

Smart card readers are tools used by large companies and organizations for enhanced security authentication. These readers are designed to connect to the microprocessor of a smart card, which can contain either memory cards with non-volatile memory storage and specific security logic or microprocessor cards with volatile memory and microprocessor components.

A scanner is an optical input device that utilizes light to convert images on paper into a digital form for storage on a computer. Scanners are essential for preserving documents in their original form for future modifications and can save images in both gray scale and color modes.

Printer speed is commonly measured in Pages Per Minute (PPM), indicating how many pages a printer can produce in a minute. Resolution in a printer is measured in Dots Per Inch (DPI), which signifies the level of detail that can be printed. Higher DPI values result in clearer and more detailed prints, while lower DPI values might lead to less sharp images.

A plotter's primary function among output devices is to generate vector graphics. Unlike regular printers which focus on text and images, plotters are specialized for creating precise and detailed drawings, often used for architectural plans, mechanical blueprints, and designs requiring high precision. They utilize tools like pens, pencils, or markers to produce these vector graphics accurately.

A speaker functions as an output device by receiving sound in the form of electric current. When connected to a sound card in a computer system, it converts electrical signals into audible sound waves. This enables users to listen to music, participate in presentations, or engage with audio content through their computer systems.

The key difference between a drum plotter and a flatbed plotter lies in their design and functionality. Drum plotters feature a rotating drum on which the paper is mounted and moved, allowing for continuous plotting and precise drawings. In contrast, flatbed plotters have a stationary flat surface where the paper remains fixed, and the plotting device moves to create the drawings. This difference in movement affects the precision and speed of plotting between the two types of devices.

Projectors are commonly used in classrooms or large meeting rooms to show a temporary display for many people to see at once. They are essential for sharing information, presentations, videos, and more in a way that is visible to a large audience simultaneously.

A Serial Port sends data bit by bit through a single wire, making it slower compared to other types of ports. Although slower, serial ports are still used for specific devices like modems, plotters, and barcode readers where speed may not be the primary concern.

The Parallel Port is commonly used for connecting printers because it can send eight bits of data simultaneously, enabling fast transmission of data. This feature makes it ideal for devices like printers that require quick and efficient data transfer.

A Smart Card Reader is a tool designed to connect to the microprocessor of a smart card. This connection allows for the reading and processing of data stored on the smart card. Smart cards typically contain important information and security logic, and the reader facilitates access to this data by establishing a connection to the microprocessor within the card.

Impact printers, such as Dot Matrix and Daisy Wheel printers, work by physically hitting a paper and ribbon to create characters, akin to a typewriter. On the other hand, Non-Impact printers like Inkjet and Laser printers use different technologies like spraying ink droplets or laser beams to create prints without any physical impact. This distinction in printing methods is crucial for understanding how these different printer types operate and produce printouts.

The primary purpose of a projector in a classroom or large meeting room setting is to show a temporary display to a large audience. Projectors are essential for allowing a group of people to view computer information or presentations simultaneously on a big screen. This facilitates effective communication and information sharing in educational and professional settings.

LCD monitors, also known as Liquid Crystal Display monitors, are commonly used to display visual information on computers. They come in both monochrome and color variations, with color displays capable of showing 256 colors simultaneously. The quality of the image displayed on an LCD monitor depends on factors like resolution, dot pitch, and refresh rate.

The primary purpose of headphones, when connected to a sound source like an audio amplifier or media player, is to enhance sound quality for the user. By delivering audio signals directly to the ears, headphones provide a more immersive and private listening experience, isolating the user from external noise and improving the clarity and fidelity of the audio being played.