ISC class XI Practice Test 1

Part I (10 marks)

(Attempting all the answers in this part is compulsory)

1. Convert the following Hexadecimal to binary & decimal [4]
   1. F8     b.   1A        c.  3B                   d.   ACE
2. Perform binary multiplication on the following                     [2]
   1. 1010*101           b.1101*0101
3. Convert the following into decimal                                              [4]
   1. 1101010    b. 01.111   c. 1001.00101    d. 1010111

Part II (20 marks)

(Attempt any two questions)

Question1.                         

1. Explain with logic gate diagram why NAND & NOR gates are called universal gates?                                                [5]
2. Explain Full adder circuit with help of logic gate diagram, truth table, Boolean expression?                                      [5]

                                                                                   

1. Draw logic gate diagram of (x+y+z).(x’+y+z’) using basic gates.       [4]
2. Explain what is truth table?                                                 [2] 
3. Draw logic gate diagram for the following using NOR gate
   1. P’Q’+PQ+QR                           [4]

Q3                                                             

1. Prove that for the following using truth table?                  [4]
   1. A.(A+B)=A
   2. (A.B).A’=0
2. Expand the following                                   [3]

• ASCII
• EBCDIC
• ISCII 3. Explain the rule for binary subtraction?                    [3]