1. Which one of the following octal numbers would be obtained on converting the binary number 1010111 to a base 8 number?
(a) 531
(h) 721
(c) 67
(d) 127
2. What will be displayed when the following C code segment is executed?
#include<stdio.h>
int main()
{
int a[5] = {5, 1, 15, 20, 25};
int i, j, m;
i = ++a[1];
j = a[1]++;
m = a[i++];
printf("%d, %d, %d", i, j, m);
return 0;
}
(a) 2, 1, 15
(b) 1, 2, 5
(c) 3, 2, 15
(d) 2, 3, 20
3. Which of the following protocol is used to retrieve emails?
(a) SMTP
(b) POP3
(c) FTP
(d) SNMP
4. Which one of the following most correctly describes the functionality of the control unit in a CPU?
(a) To perform arithmetic operations based on decoded program instructions
(b) To store program instructions
(c) To perform logic operations based on decoded program instructions
(d) To generate control signals based on decoded program instructions
5. Which one among the following is the smallest integer that can be represented in 2’s complement form using 8-bits?
(a) -256
(b) -128
(c) -127
(d) 0
6. In the memory hierarchy of a computer, which one of the following is the fastest memory?
(a) SRAM
(b) DRAM
(c) Registers
(d) Flash memory
7. Which one of the following is not a characteristic of DRAMs?
(a) High density
(b) Low cost
(c) High speed
(d) Volatile
8. A combinational logic circuit that sends data coming from a single source to two or more separate destinations is called one of the following?
(a) Decoder
(b) Encoder
(c) Multiplexer
(d) Demultiplexer
9. What is the binary representation of the decimal value 0.125?
(a) 0.11
(i) 0.01
(c) 0.001
(d) 0.011
10. A file has a size of 10 KBytes. What is the size of the file in bits?
(a) 10,000
(b) 81,920
(c) 10,240
(d) 80,240
Answers
1. (d). (1010111)₂ = (127)₈
Step 1: Write down the binary number (001010111)₂. Group all the digits in sets of three starting from the LSB (far right). Add zeros to the left of the last digit if there aren't enough digits to make a set of three.
001 010 111
Step 2: Use the table below to convert each set of three into an octal digit.
In this case,
001 = 1, 010 = 2, 111 = 7.
So, the number 1010111 in binary is equivalent to 127 in octal.
2. (c)
Step 1: int a[5] = {5, 1, 15, 20, 25}; The variable arr is declared as an integer array with a size of 5 and it is initialized to
a[0] = 5, a[1] = 1, a[2] = 15, a[3] = 20, a[4] = 25 .
Step 2: int i, j, m; The variables i, j, m are declared as an integer type.
Step 3: i = ++a[1]; becomes i = ++1; Hence i = 2 and a[1] = 2
Step 4: j = a[1]++; becomes j = 2++; Hence j = 2 and a[1] = 3.
Step 5: m = a[i++]; becomes m = a[2]; Hence m = 15 and i is incremented by 1(i++ means 2++ so i=3)
Step 6: printf("%d, %d, %d", i, j, m); It prints the value of the variables i, j, m
Hence the output of the program is 3, 2, 15
3. (b) Simple Mail Transfer Protocol (SMTP) is a push protocol and is used to send the mail whereas post office protocol (POP) or IMAP (internet message access protocol) are used to retrieve those mails at the receiver’s side.
4. (c) The central processing unit (CPU) of a computer is a piece of hardware that carries out the instructions of a computer program. It performs the basic arithmetical, logical, and input/output operations of a computer system.
5. (b)
6. (c) In a computer, a register is the fastest memory. Register a part of the computer processor which is used to hold a computer instruction, perform the mathematical operation as storage address, or any kind of data.
7. (c) Dynamic random access memory (DRAM) is a type of semiconductor memory that is typically used for the data or program code needed by a computer processor to function. DRAM is a common type of random access memory (RAM) that is used in personal computers (PCs), workstations and servers. Random access allows the PC processor to access any part of the memory directly rather than having to proceed sequentially from a starting place. RAM is located close to a computer's processor and enables faster access to data than storage media such as hard disk drives and solid-state drives.
8. (d) A demultiplexer (also known as a demux or data distributor) is defined as a circuit that can distribute or deliver multiple outputs from a single input. A demultiplexer can perform as a single input with many output switches.
9. (c)
Step 1: We multiply 0.125 by 2 and take the integer part
0.125 x 2 = 0.250
Integer part = 0
Fractional part = 0.250
As the fractional part is not equal to 0 so we copy it to the next step.
Step 2: We multiply 0.250 by 2 and take the integer part
0.250 x 2 = 0.500
Integer part = 0
Fractional part = 0.500
As the fractional part is not equal to 0 so we copy it to the next step.
Step 3: We multiply 0.500 by 2 and take the integer part
0.500 x 2 = 1.000
Integer part = 1
Fractional part = 0
Now the fractional part is 0 so, we stop here.
The calculated integer part is as followed.
Step 1: 0
Step 2: 0
Step 3: 1
To find the binary we have to scan the integer part from top
So, 0.125(base 10) = 0.001(base 2)
10. (b) Hint: 1 Byte = 8 Bit and 1 Kilobyte = 1,024 Bytes
---
Comments