4th Class Computers Science Characteristics of Memory Devices Access Time

       Access Time

Access time is the time required between the requests made for read/write operations and the time it takes for the completion of the request. Generally, it is measured for read operations only. The access time depends upon the physical characteristics and the access modes used for that device. Primary memory has a faster access time as compared to secondary memory. The time taken to access a given byte of information stored on a hard disk is typically a few thousandths of a second or milliseconds. By contrast, the time taken to access a given byte of information stored in random access memory is measured in billionths of a second or nano seconds. In disk drives, disk access time is the time required for a computer to process data from the processor and then retrieves the required data from a storage device, such as a hard drive.  

 Sam and Peter are discussing about the accessing time of a computer. Read their conversation and identify who is correct.

Sam: Access time is the time required for completing a file on which you are working. And it is measured for write operations only.

Peter: The access time depends upon the physical characteristics and the access modes used for that device.

(A) Sam is correct                                            

(B) Peter is correct

(C) Both are partially correct                      

(D) Both of them are correct

(E) None of them are correct  

Answer: (B)

Explanation

Correct Option:

(B) Statement of Peter is correct about access time of a computer.

Incorrect Options:

(A) Statement of Sam is incorrect about access time of a computer. Therefore, option (A) is incorrect.

(C) Sam is fully correct whereas Peter is fully incorrect. Therefore, option (C) is incorrect.

(D) Both of them are not correct. Only Sam is correct. Therefore, option (D) is incorrect.

(E) Both of them are not incorrect. Only Peter is incorrect. Therefore, option (E) is incorrect.    

 Given below are the statements about the computer memory. Select the correct statement.

1. Secondary memory has a faster access time as compared to primary memory.

2. The time taken to access a given byte of information stored on a hard disk is typically a few thousandths of a second.

3. In disk drives, disk access time is the time required for a computer to process data from the processor and then retrieves the required data from a storage device.  

(A) 1 and 2                                        

(B) 2 and 3

(C) 1 and 3                                                          

(D) All of these

(E) None of these  

Answer: (b)

Explanation

Correct Option:

(B) Statements 2 and 3 are correct.

Incorrect Options:

(A) Statement 1 is incorrect and statement 2 is correct. Therefore, option (A) is incorrect,

(C) Statement 1 is incorrect and statement 3 is correct. Therefore, option(C) is incorrect.

(D) All the given statements are not correct. Therefore, option (D) is incorrect.

(E) All the given statements are not incorrect. Therefore, option (E) is incorrect.