OPERATING SYSTEM MCQS PART 12

OPERATING SYSTEM MCQS PART 12

1. An OR gate has 4 inputs. One input is high and the other three are low. The output is …….
1. Low        
2. High           
3. alternately     
4. high and low may be high or low depending on relative magnitude of inputs
Answer : 2
Explanation: In OR any input high means high output.

2. Decimal number 10 is equal to binary number ……………
1. 1110            
2. 1010        
3. 1001          
4. 1000
Answer : 2
Explanation: 1010 = 8 + 2 = 10 in decimal.

 
3. Both OR and AND gates can have only two inputs.
1. True          
2. False
Answer : 2
Explanation:  Any number of inputs are possible.

4. A device which converts BCD to seven segments is called ……..
1. Encoder
2. Decoder
3. Multiplexer
4. None of these
Answer : 2
Explanation:  Decoder converts binary/BCD to alphanumeric.

5. In 2’s complement representation the number 11100101 represents the decimal number …………
1. +37            
2. -31       
3.+27         
4.-27
Answer : 4
Explanation:  
A = 11100101. Therefore Ā = 00011010 and A’ = Ā + 1 = 00011011 = 16 + 8 + 2 + 1 = 27. Therefore A = -27.

6. A decade counter skips ………..
1. binary states 1000 to 1111    
2. binary states 0000 to 0011
3. binary states 1010 to 1111    
4. binary states 1111 to higher
Answer : 3
Explanation:  A decade counter counts from 0 to 9. It has 4 flip-flops. The states skipped are 10 to 15 or 1010 to 1111.

7. BCD input 1000 is fed to a 7 segment display through a BCD to 7 segment decoder/driver. The segments which will lit up are ………….
1. a, b, d         
2. a, b, c               
3. all          
4. a, b, g, c, d
Answer : 3
Explanation:  1000 equals decimal 8 Therefore all segments will lit up.

8. A ring counter with 5 flip flops will have ………. states.
1. 5               
2. 10                 
3. 32              
4. Infinite
Answer : 1

9. In the expression A + BC, the total number of minterms will be ………
1. 2                   
2. 3                
3. 4                  
4. 5
Answer : 4

10. Which of the following is non-saturating?
1. TTL                 
2. CMOS                 
3. ECL               
4. Both 1 and 2
Answer : 3