II. Short Answers
Question 1. What is a computer?
Answer: "A Computer is an electronic device that takes
raw data (unprocessed) as an input from the user and processes it under the
control of a set of instructions (called program), produces a result (output),
and saves it for future use."
Answer: Data: Data is defined as an unprocessed collection
of raw facts, suitable for communication, interpretation or processing.
Eg: 134, 16, 'Kavitha' C" are data. This will not give
any meaningful message.
Information: Information is a collection of facts from which
conclusions may be drawn. Eg: Kavitha is 16 years old.
Answer: The CPU has three components which are Control Unit,
Arithmetic and Logic Unit (ALU) and Memory Unit.
Answer: The ALU is a part of the CPU where various computing
functions are performed on data. The ALU performs arithmetic operations such as
addition, subtraction, multiplication, division and logical operations. The
result of an operation is stored in internal memory of CPU. The logical
operations of ALU promote the decision-making ability of a computer.
Answer: The control unit controls the flow of data between
the CPU, memory and I/O devices. It also controls the entire operation of a
computer.
Answer: The memory unit is of two types which are primary
memory and secondary memory. The primary memory is used to temporarily store
the programs and data when the instructions are ready to execute. The secondary
memory is used to store the data permanently.
Answer: Input unit: Input unit is used to feed data to the
computer, initially which can be stored in the memory unit for further
processing. Eg: Keyboard, Mouse, etc.
Output unit: An output unit is any hardware component that
conveys information in user’s understandable form. Eg: Printer, Plotter etc.
Answer: Primary memory:
1. It is used to temporarily store the programs and data
when the instructions are ready to execute. 2. It is a volatile memory that is,
the content is lost when the power supply is switched off. 3. Eg: Random Access
Memory (RAM)
Secondary memory:
1. It is used to store the data permanently. 2. It is a non-volatile
memory that is, the content is available even after the power supply is
switched off. 3. Eg: Hard disk, CD-ROM and DVD ROM.
III. Explain in Brief
Answer: The general characteristics of computers are speed,
memory capacity, accuracy, diligence, representatives, reliability,
endurance and versatility.
Answer: The applications of computers are business,
education, marketing, banking, insurance, communication, health care, military,
engineering design.
Answer: The input device is the component through which data
and instructions are provided to the computer. Eg: Keyboard and mouse.
Answer: The output device is the component which delivers
the data and information proceed by the CPU. Eg: Monitor, plotter, printers.
Answer: Optical Mouse:
1. It uses Red, Blue or Green led. 2. It has three buttons.
3. It is less sensitive and sensitive towards surface.
Laser Mouse:
1. It use only infrared led.
2. It has as many as 12 buttons and can be programmed by
user.
3. It is highly sensitive and able to work on any hard
surface.
Answer: These printers print with striking of hammers or
pins on ribbon. These printers can print on multi-part (using carbon papers) by
using mechanical pressure.
Eg: Dot Matrix printers and Line matrix printers.
A Dot matrix printer that prints using a fixed number of
pins or wires. Each dot is produced by a tiny metal rod, also called a
"wire" or "pin", which works by the power of a tiny
electromagnet or solenoid, either directly or through a set of small levers. It
generally prints one line of text at a time. The printing speed of these
printers varies from 30 to 1550 CPS (Character per Second).
Line matrix printers use a fixed print head for printing.
Basically, it prints a page-wide line of dots. But it builds up a line of text
by printing lines of dots. Line printers are capable of printing much more than
1000 Lines Per Minute, resulting in thousands of pages per hour. These printers
also uses mechanical pressure to print on multi-part (using carbon papers).
Answer:
1. Parallel and Distributed computing.
2. Computers have become smarter, faster and smaller.
3. Development of robotics.
4. Natural Language Processing.
5. Development of Voice Recognition Software.
Answer: Monitor is the most commonly used output device to
display the information. It looks like a TV, Pictures on a monitor are formed
with picture elements called Pixels. Monitors may either be Monochrome which
display text or images in Black and White or can be colour, which display
results in multiple colours.
There are many types of monitors available such as CRT
(Cathode Ray Tube), LCD (Liquid Crystal Display) and LED (Light Emitting
Diodes). The monitor works with the VGA (Video Graphics Array) card. The video
graphics card helps the keyboard to communicate with the screen. It acts as an
interface between the computer and display monitor. Usually the recent
motherboards incorporate built-in video card.
Question 1. Explain the basic components of a computer with
a neat diagram?
Answer: The computer is the combination of hardware and
software. Hardware is the physical component of a computer like motherboard,
memory devices, monitor, keyboard etc., while software is the set of programs
or instructions. Both hardware and software together make the computer system
function.
Input device: Input unit is used to feed any form of data to the computer, which can be stored in the memory unit for further processing. Eg: Keyboard, mouse, etc.
Central processing unit (CPU): CPU is the major component
which interprets and executes software instructions. It also control the
operation of all other components such as memory, input and output units. It
accepts binary data as input, process the data according to the instructions
and provide the result as output. The CPU has three components which are
Control unit, Arithmetic and logic unit (ALU) and Memory unit.
(i) Arithmetic and Logic Unit:
The ALU is a part of the CPU where various computing
functions are performed on data. The ALU performs arithmetic operations such as
addition, subtraction, multiplication, division and logical operations. The
result of an operation is stored in internal memory of CPU. The logical
operations of ALU promote the decision making ability of a computer.
(ii) Control Unit:
The control unit controls the flow of data between the CPU,
memory and I/O devices. It also controls the entire operation of a computer.
Output Unit: An Output Unit is any hardware component that
conveys information to users in an understandable form. Example: Monitor,
Printer etc.
Memory Unit the Memory Unit is of two types which are
primary memory and secondary memory. The primary/ memory is used to temporarily
store the programs and data when the instructions are ready to execute. The
secondary memory is used to store the data permanently.
(i) The Primary Memory is volatile, that is, the content is
lost when the power supply is switched off. The Random Access Memory (RAM) is
an example of a main memory.
(ii) The Secondary memory is non-volatile, that is, the
content is available even after the power supply is switched off. Hard disk,
CD-ROM and DVD ROM are examples of secondary memory.
Answer: Growth in the computer industry is determined by the
development in technology. Based on various stages of development, computers
can be divided into different generations.
Question 3. Explain the following:
1. Inkjet Printer
2. Multimedia projector
3. Bar code
4. QR code Reader.
They use the technology of firing ink by heating it so that
it explodes towards the paper in bubbles or by using piezoelectric in which
tiny electric currents controlled by electronic circuits are used inside the
printer to spread ink in jet speed. An Inkjet printer can spread millions of dots
of ink at the paper every single second.