Q.12. What are input-output devices?(2012)
Ans. The input-output devices are used to input data and instructions and output the results. Inputoutput devices provide the means of communication between the computer system and the outer world. They are also known as peripheral devices.
Q.13. Write down any two functions of input devices.
Ans. The two functions of input devices are as follows:
1. The input devices convert the instructions and data into a form that computer can understand
(in binary form).
2. Finally, the input devices supply the converted data and instructions to the computer system for further processing.
Q.14. Describe the three main characteristics of fifth generation computer.
Ans. The three main characteristics of fifth generation computer are as follows:
1. Consume much less power than their predecessors.
2. More reliable than their predecessors.
3. Cheaper than fourth generation computers.
Q.15. What are two main functions of output devices?
Ans. The two main functions of output devices are as follows:
1. The output devices accept the results produced by the computer in binary form.
2. The output devices convert the coded results into a human acceptable (readable) form(such as, in English, Hindi or other similar languages).
Q.16. What do you mean by memory?
Ans. A computer system has storage areas, often referred to as memory, Memory is one of the important component of the computer hardware. The memory can receive, hold and deliver data when instructed to do so.
Q.17. Define the term track ball.
Ans. A track ball is a pointing device and is similar to a mouse. The ball is normally placed on the top along with the buttons. To move the graphics cursor around the screen, the ball is simply rolled with the fingers.
Q.18. What is OCR device?
Ans. The OCR (Optical Character Recognition) is a scanning device equipped with character nition software, called OCR software. The OCR scanner scans the document and produce bitmap images of the characters and OCR software converts these bitmap images of character to equivalent ASCII codes.
Q.19. Define electronic card reader.
Ans. Electronic cards are small plastic cards having encoded data. An electronic card reader, which is connected to the computer, is an input device and is used to read the data encoded on an electronic card and transfer it to the computer for further processing.
Q.20. What do you mean by digital video camera?
Ans. A digital video camera is an input device, which takes continuous images by breaking down the images into a series of lines. Each line is scanned one at a time and the continuously varying intensities of red, green and blue light across the line.
Q.21. What is hard copy output?
Ans. Hard copy output refers to information that is produced on papers and can be read immediately or stored and read later. This is relatively stable and permanent form of output, e.g. printer and plotter.
Q.22. What is Dot-Matrix Printer (DMP)?
Ans. Dot-Matrix Printer (DMP) comes in the category of impact printer: Dot-matrix printers are also known as character printers, since they print one character at a time. Dot-matrix printer is noisy. It prints usually 30 to 600 characters per second.
Q.23. Define laser printer.
Ans. Laser printer comes in the category of non-impact printers. It is a page printer, which prints one page at a time. It has a laser beam source, a multi-sided mirror, photoconductive drum and a toner.
Q.24. What do you mean by plotter?
Ans. Many engineering design applications such as architectural plan of a building or bridge, design of mechanical components of an aircraft or a car, etc. often require high-quality, perfectlyproportioned graphic output on large sheets. A special type of hard copy output device is called a plotter. It is of two types-drum plotter and flatbed plotter.
Q.25. Write any two limitations of primary storage.
Ans. The two limitations of primary storage are:
1. As compared to secondary storage, primary storage has limited storage capacity,
2. Primary storage is costlier than the secondary storage because storing cost per bit of information is high in the primary storage.
Q.26. What are the two types of Read Only Memory (ROM)?
Ans. The two types of read only memory are:
1. Manufacturer-programmed ROM.
2. User-programmed ROM.
Q.27. Define Programmable Read Only Memory (PROM).
Ans. PROMs, which can be programmed by the user only once, are called programmable read only memory and then this PROM does not lose its information and can be read many times.
Q.28. What is RAM?
ANS. RAM consists of electronic circuits prepared on silicon chips. It is also known as read/write memory. It is popularly known as memory. The term RAM is used because each separate location inside the memory can be accessed as easily as any other locations and takes the same amount of time. R is a volatile memory. It means contents of the RAM will be lost after switching off the computer.