Right Bight 4th Edition (Computer) Class 7th

Right Bight 4^th Edition (Computer)

Class 7^th

Lesson #1        

The Data Processing Cycle

ANSWER THE FOLLOWING QUESTIONS

Q1: Describe the data-processing cycle with the help of a diagram.

Ans:

data-processing cycle

Q2: What is difference between encoding and decoding?

Ans: Encoding means converting data into a data-processing system. Decoding means the information that a code represents is made available to users.

Q3: Describe three ways in which data can be processed.

Ans: Data processing can be described into three ways input, processing and output.

Q4: What is a computerized system? Explain with an example.

Ans: A computerized system uses computers and related machines to process data and makes decisions.

Example:

In large stores, the computer can itself determine that the stocks have fallen below a certain limit. It automatically sends an email message to the supplier to send more stock .The shopkeeper has very little to do. This is a computerized system.

Q5: What is information technology?

Ans: The use of different manual and computerized devices and methods for processing information is called information technology.

Q6: Describe three advantages of a computerized system over a manual system.

Ans:

a)     Fast processing is a key feature of computerized system.

b)    Accuracy is also a feature of all computerized systems.

c)     Efficiency is another common feature of computerized system.

Q7: why is a computerized system not effective in all situations?

Ans: Because a computer cannot think itself. It cannot make decisions for which it has not been programmed.

Lesson#2

BINARY COMPUTING

ANSWER THE FOLLOWING QUESTIONS

Q1: Describe three forms of data?

Ans :      

 Numeric data consists of digits and the decimal point.

·        Alphabet data consists of a fixed set of alphabetic characters (A-Z and a-z).

·        Alpha numeric data consists of letters of the alphabet numbers and special characters like @,#and %.

Q2: What state do the digits 0 and 1 represent under the binary system?

Ans : State 1 or state 0 , depending on whether eclectic  current is passing through or not. 

Q3: Why do we use binary digits to represent the presence or absence of electronic signals?

Ans: When an electronic signal is received, it is recorded as 1 in the MU.

When no electronic signal is received, it is recorded as 0 in the MU.

Q4: What is a bit?

Ans: An electronic signal, when stored, is called a bit.

Q5: Convert the following decimal numbers into binary equivalents?

     (A)27                             (B) 15

Ans :

     

Q6: Convert the following binary numbers into decimal equivalents.

      (a)    110111                                             (b) 110010

Ans : (a) 110111

=(1 x 2⁵)+(1 x 2⁴)+(0 x 2³)+(1 x 2²)+(1 x 2¹)+(1 x 2⁰)

=32+16+0+4+2+1=55

110111=55

    

    (b) 1100100

=(1 x 2⁶)+ (1 x 2⁵)+(0 x 2⁴)+(0 x 2³)+(1 x 2²)+(0 x 2¹)+(0 x 2⁰)

=64+32+0+0+4+0+0=100

1100100=100

Q7: Perform the following binary arithmetic operations?

    (a)  101+111               (b) 1101-0011

Ans:  

     

Lesson#3

System software                                       

ANSWER THE FOLLOWING QUESTIONS

Q1: Define system software. Name three categories of system software.

Ans: System software is a set of programs that enable a computer to perform routine tasks. Three categories of system software are starting up, managing files, and shutting down.

Q2: Describe three functions of an operating system.

Ans:  Three functions of an operating system are:

     a)     Booting up and providing a user interface.

     b)    Managing programs.

     c)     Managing files and directories.

Q3: What is the function of a device driver?

Ans: The device driver is a program that automatically runs the system devices attached to the computer.

Q4: What is disk failure? How can we avoid data loss as a result of disk failure?

Ans: The entire data stored on the hard disk is lost called disk failure. Back-up software helps avoid permanent data loss in such situations.

Q5: What is meant by debugging?

Ans: The process of removing errors from a program is called debugging.