set-5

201. A combinational logic circuit which generates a particular binary word or number is:

1. $\text{Decoder}$
2. $\text{Encoder}$
3. $\text{Multiplexer}$
4. $\text{De-multiplexer}$

202. Parallel adders are:

1. $\text{Combinational logic circuits}$
2. $\text{Sequential logic circuits}$
3. $\text{Both of the above}$
4. $\text{None of the above}$

203. A de-multiplexer is also known as:

1. $\text{Data selector}$
2. $\text{Multiplexer}$
3. $\text{Data distributor}$
4. $\text{Encoder}$

204. A multiplexer is known as:

1. $\text{Coder}$
2. $\text{Data selector}$
3. $\text{Decoder}$
4. $\text{Encoder}$

205. A flip-flop can store:

1. $\text{One bit of data}$
2. $\text{Three bits of data}$
3. $\text{Two bits of data}$
4. $\text{Any number of bits of data}$

206. Which of the following input combinations is not allowed in an SR flip-flop?

1. $S=0, R=0$
2. $S=1, R=0$
3. $S=0, R=1$
4. $S=1, R=1$

207. When an inverter is placed between both inputs of an SR flip-flop, the resulting flip-flop is:

1. $\text{JK flip-flop}$
2. $\text{T flip-flop}$
3. $\text{D flip-flop}$
4. $\text{Master-slave JK flip-flop}$

208. The clock signals are used in sequential logic circuits to:

1. $\text{Tell the time of the day}$
2. $\text{Tell how much time has elapsed since the system was turned on}$
3. $\text{Carry serial data signals}$
4. $\text{Synchronize events in various parts of a system}$

209. What logic function is obtained by adding an inverter to the output of an AND gate?

1. $\text{OR}$
2. $\text{XOR}$
3. $\text{NAND}$
4. $\text{NOR}$

210. The simplified form of the Boolean expression ( (X + Y + XY)(X + Z) ) is:

1. $X + Y + Z$
2. $X + YZ$
3. $XY + YZ$
4. $XZ + Y$

211. The highest decimal number that can be represented with 10 binary digits is:

1. $1023$
2. $512$
3. $1024$
4. $2048$

212. What is the hexadecimal equivalent of the binary number 10101111?

1. $AF$
2. $8C$
3. $OF$
4. $All of the above$

213. Which of the following logic families has the highest noise immunity?

1. $\text{RTL}$
2. $\text{TTL}$
3. $\text{DTL}$
4. $\text{HTL}$

214. Pick up the wrong logical expression:

1. $1 + 0 = 0 + 1 = 1$
2. $X + Y = X \cdot Y$
3. $0 + 0 = 1 \cdot 1 = 0$
4. $X + 0 = X$

215. In a four-input NAND gate, all but one input is 1. The output is:

1. $4$
2. $1$
3. $0$
4. $\text{Undefined}$

216. In a four-input AND gate, all but one input is 1. The output is:

1. $0$
2. $1$
3. $\text{Undefined}$
4. $4$

217. According to the Idempotent law, ( X + X = ):

1. $1$
2. $X$
3. $0$
4. $X \cdot X$

218. According to the Idempotent law, ( X \cdot X = ):

1. $1$
2. $X$
3. $0$
4. $X + X$

219. The output will be one in case any input is one in the case of:

1. $\text{OR gate}$
2. $\text{NAND gate}$
3. $\text{AND gate}$
4. $\text{NOT gate}$

220. Which of the following circuits is known as a half adder?

1. $\text{EXCLUSIVE AND circuit}$
2. $\text{INCLUSIVE OR circuit}$
3. $\text{Flip-flop circuit}$
4. $\text{EXCLUSIVE OR circuit}$

221. Which of the following functions is referred to as the complementary function?

1. $\text{OR function}$
2. $\text{NAND function}$
3. $\text{NOT function}$
4. $\text{AND function}$

222. Which of the following statements illustrates the distributive law?

1. $(A + B) + C = A + (B + C) = A + B + C$
2. $(A \cdot B) \cdot C = A \cdot (B \cdot C) = A \cdot B \cdot C$
3. $A + B = B + A$
4. $A \cdot (B + C) = (A \cdot B) + (A \cdot C)$

223. Which of the following is termed as the minimum error code?

1. $\text{Binary code}$
2. $\text{Excess-3 code}$
3. $\text{Gray code}$
4. $\text{Octal code}$

224. For which of the following flip-flops is the output clearly defined for all combinations of two inputs?

1. $\text{D-type flip-flop}$
2. $\text{JK flip-flop}$
3. $\text{R-S flip-flop}$
4. $\text{T flip-flop}$

225. A 4-bit shift register can be made by using:

1. $3 \text{ JK flip-flops}$
2. $5 \text{ JK flip-flops}$
3. $4 \text{ JK flip-flops}$
4. $8 \text{ JK flip-flops}$

226. Which of the following statements is false?

1. $\overline{A \cdot B} = \overline{A} + \overline{B}$
2. $\overline{A + B} = \overline{A} \cdot \overline{B}$
3. $A + B = \overline{A} \cdot \overline{B}$
4. $A + A = A$

227. The minimum form of the expression ( (A + B)(A + B + C) ) is:

1. $A + C$
2. $A + B$
3. $A + B + C$
4. $A + BC$

228. One’s complement of 1011.01 is:

1. $0100.10$
2. $1011.10$
3. $0100.11$
4. $0100.01$

229. The NAND gate output will be low if the two inputs are:

1. $00$
2. $10$
3. $01$
4. $11$

230. What is the binary equivalent of the decimal number 368?

1. $101110000$
2. $111010000$
3. $110110000$
4. $111100000$

231. The decimal equivalent of the hexadecimal number 1A53 is:

1. $6793$
2. $6973$
3. $6739$
4. $6379$

232. The octal equivalent of the decimal number 324.987 is:

1. $504.771$
2. $815.234$
3. $640.781$
4. $90.987$

233. The simplification of the Boolean expression ( (A \cdot B \cdot C) + (A \cdot B \cdot \overline{C}) ) is:

1. $0$
2. $A$
3. $A \cdot B$
4. $B \cdot C$

234. The number of control lines for an 8-to-1 multiplexer is:

1. $2$
2. $4$
3. $3$
4. $5$

235. How many flip-flops are required for a mod-16 counter?

1. $5$
2. $3$
3. $4$
4. $6$

236. EPROM contents can be erased by exposing it to:

1. $\text{Ultraviolet light}$
2. $\text{Burst of microwaves}$
3. $\text{Infrared rays}$
4. $\text{Intense heat radiations}$

237. The hexadecimal number ‘A0’ has the decimal value equivalent to:

1. $80$
2. $100$
3. $256$
4. $160$

238. The Gray code for decimal number 6 is equivalent to:

1. $1100$
2. $0101$
3. $1001$
4. $0110$

239. The Boolean expression ( A \cdot B + A \cdot \overline{B} + \overline{A} \cdot B ) is equivalent to:

1. $A + B$
2. $A \cdot B$
3. $\overline{A} + \overline{B}$
4. $A \oplus B$

240. The 2’s complement of the binary number 1101101 is:

1. $0010011$
2. $0010010$
3. $0010001$
4. $0010000$

241. The digital logic family which has minimum power dissipation is:

1. $\text{TTL}$
2. $\text{DTL}$
3. $\text{RTL}$
4. $\text{CMOS}$

242. The output of a logic gate is 1 when all its inputs are at logic 0. The gate is either:

1. $\text{NAND or EX-OR}$
2. $\text{AND or EX-OR}$
3. $\text{OR or EX-NOR}$
4. $\text{NOR or EX-NOR}$

243. Data can be changed from special code to temporal code by using:

1. $\text{Shift registers}$
2. $\text{Combinational circuits}$
3. $\text{Counters}$
4. $\text{Multiplexers}$

244. A ring counter consisting of five flip-flops will have:

1. $5 \text{ states}$
2. $32 \text{ states}$
3. $10 \text{ states}$
4. $\text{Infinite states}$

245. The speed of conversion is maximum in:

1. $\text{Successive-approximation A/D converter}$
2. $\text{Parallel-comparator A/D converter}$
3. $\text{Counter-ramp A/D converter}$
4. $\text{Dual-slope A/D converter}$

246. The 2’s complement of the number 1101101 is:

1. $0010011$
2. $0010010$
3. $0010001$
4. $0010000$

247. The correction to be applied in a decimal adder to the generated sum is:

1. $A + B$
2. $A \cdot B$
3. $\overline{A} + \overline{B}$
4. $\overline{A} \cdot \overline{B}$

248. When simplified with Boolean algebra, ( (x + y)(x + z) ) simplifies to:

1. $x$
2. $x + yz$
3. $x + y + z$
4. $x(y + z)$

249. The gates required to build a half adder are:

1. $\text{EX-OR gate and NOR gate}$
2. $\text{EX-OR gate and AND gate}$
3. $\text{EX-OR gate and OR gate}$
4. $\text{Four NAND gates}$

250. The code where all successive numbers differ from their preceding number by a single bit is:

1. $\text{Binary code}$
2. $\text{Excess-3 code}$
3. $\text{BCD code}$
4. $\text{Gray code}$