Select Page
Generic selectors
Exact matches only
Search in title
Search in content
Search in posts
Search in pages
Filter by Categories
nmims post
Objective Type Set
Online MCQ Assignment
Question Solution
Solved Question
Uncategorized

# Multiple choice question for engineering

## Set 1

1. Ring shift and Johnson counters are:
a) Synchronous counters
b) Asynchronous counters
c) True binary counters
d) Synchronous and true binary counters

Answer: a [Reason:] Since, all of the clock inputs are connected through a single clock pulse in ring shift and johnson counters. So, both are synchronous counters.

2. What is the difference between a shift-right register and a shift-left register?
a) There is no difference
b) The direction of the shift
c) Propagation delay
d) The clock input

Answer: b [Reason:] In shift-right register, shifting of bit takes place towards right and towards left for shift-left register.

3. What is a transceiver circuit?
a) A buffer that transfers data from input to output
b) A buffer that transfers data from output to input
c) A buffer that can operate in both directions
d) None of the Mentioned

Answer: c [Reason:] A transceiver circuit is a buffer that can operate in both directions right as well as left.

4. A 74HC195 4-bit parallel access shift register can be used for
a) Serial in/serial out operation
b) Serial in/parallel out operation
c) Parallel in/serial out operation
d) All of the Mentioned

Answer: d [Reason:] 74HC195 is an IC, which can be used for all of the given operations.

5. Which type of device may be used to interface a parallel data format with external equipment’s serial format?
a) Key matrix
b) UART
c) Memory chip
d) Series in Parallel out

Answer: a [Reason:] UART means Universal Asynchronous Receiver/Transmitter which converts the bytes it receives from the computer along parallel circuits into a single serial bit stream for outbound transmission.

6. What is the function of a buffer circuit?
a) To provide an output that is inverted from that on the input
b) To provide an output that is equal to its input
c) To clean up the input
d) To clean up the output

Answer: b [Reason:] The function of a buffer circuit is to provide an output that is equal to its input.

7. What is the preset condition for a ring shift counter?
a) All FFs set to 1
b) All FFs cleared to 0
c) A single 0, the rest 1
d) A single 1, the rest 0

Answer: d [Reason:] In preset condition all of the bits are 0 except first one.

8. Which is not characteristic of a shift register?
a) Serial in/parallel in
b) Serial in/parallel out
c) Parallel in/serial out
d) Parallel in/parallel out

Answer: a [Reason:] There is no such type of register present who doesn’t have output end.

9. To keep output data accurate, 4-bit series-in, parallel-out shift registers employ a
a) Divide-by-4 clock pulse
b) Sequence generator
c) Strobe line
d) Multiplexer

Answer: c [Reason:] n computer or memory technology, a strobe is a signal that is sent that validates data or other signals on adjacent parallel lines.

10. Another way to connect devices to a shared data bus is to use a
a) Circulating gate
b) Transceiver
c) Bidirectional encoder
d) Strobed latch

Answer: b [Reason:] A transceiver is a device comprising both a transmitter and a receiver which are combined and share common circuitry or a single housing. When no circuitry is common between transmit and receive functions, the device is a transmitter-receiver.

## Set 2

1. What is a recirculating register?
a) Serial out connected to serial in
b) All Q outputs connected together
c) A register that can be used over again
d) None of the Mentioned

Answer: a [Reason:] A recirculating register is a register whose serial output is connected to the serial input in a circulated manner.

2. When is it important to use a three-state buffer?
a) When two or more outputs are connected to the same input
b) When all outputs are normally HIGH
c) When all outputs are normally LOW
d) When two or more outputs are connected to two or more inputs

Answer: a [Reason:] When two or more outputs are connected to the same input, in such situation we use of tristate buffer always because it has capability to take upto three inputs.

3. A bidirectional 4-bit shift register is storing the nibble 1110. Its input is LOW. The nibble 0111 is waiting to be entered on the serial data-input line. After two clock pulses, the shift register is storing ________
a) 1110
b) 0111
c) 1000
d) 1001

Answer: d [Reason:] Stored nibble | waiting nibble 0111 | 1110, Initially 111 | 1100, 1st pulse 11 | 1001, 2nd pulse.

4. In a parallel in/parallel out shift register, D0 = 1, D1 = 1, D2 = 1, and D3 = 0. After three clock pulses, the data outputs are ________
a) 1110
b) 0001
c) 1100
d) 1000

Answer: b [Reason:] Parallel in parallel out gives the same output as input.

5. The group of bits 10110111 is serially shifted (right-most bit first) into an 8-bit parallel output shift register with an initial state 11110000. After two clock pulses, the register contains
a) 10111000
b) 10110111
c) 11110000
d) 11111100

Answer: d [Reason:] It can be solved as per the explanation given for question number 3.

6. By adding recirculating lines to a 4-bit parallel-in serial-out shift register, it becomes a ________, ________, and ________out register.
a) Parallel-in, serial, parallel
b) Serial-in, parallel, serial
c) Series-parallel-in, series, parallel
d) Bidirectional in, parallel, series

Answer: a [Reason:] One bit shifting takes place just after the output obtained on every register. Hence, by adding recirculating lines to a 4-bit parallel-in serial-out shift register, it becomes a Parallel-in, Serial, and Parallel-out register.

7. What type of register would have a complete binary number shifted in one bit at a time and have all the stored bits shifted out one at a time?
a) Parallel-in Parallel-out
b) Parallel-in Serial-out
c) Serial-in Parallel-out
d) Serial-in Serial-out

Answer: c [Reason:] Serial-in Serial-out register would have a complete binary number shifted in one bit at a time and have all the stored bits shifted out one at a time.

8. In a 4-bit Johnson counter sequence there are a total of how many states, or bit patterns?
a) 1
b) 3
c) 4
d) 8

Answer: d [Reason:] In johnson counter, number of states are determined by 2N. So, 2*4 = 8.

9. If a 10-bit ring counter has an initial state 1101000000, what is the state after the second clock pulse?
a) 1101000000
b) 0011010000
c) 1100000000
d) 0000000000

Answer: b [Reason:] After shifting 2-bit we get the output as 0011010000 (Since, two zeros are at 1st position which came from the last two bits).

10. How much storage capacity does each stage in a shift register represent?
a) One bit
b) Two bits
c) Four bits
d) Eight bits

Answer: a [Reason:] A shift register has the capability to store one bit and if another bit is to store, in such situation it deletes the previous data and stores them.

## Set 3

1. Smoker proposed an analytical closed form formula, to calculate
a) Reflux ratio
b) Number of trays
c) Number of stages
d) Number of feeds

Answer: b [Reason:] In 1938, Smoker proposed an analytical closed form formula to calculate the number of stages in a binary distillation column.

2. The analytical formula fails to predict the
a) Equilibrium Stages
b) Reflux ratio
c) Feed inlet and outlet
d) Boil up

Answer: a [Reason:] The analytical formula fails to predict the Equilibrium Stages with reasonable accuracy, while reflux and boil up are predicted as ratio.

3. In the below diagram, the minimum reflux can be seen as ______ using smoker’s equation.

a) 1.567
b) 1.425
c) 1.2
d) Can’t be specified

Answer: b [Reason:] By tracking the locus to the x axis of smoker’s line reflux is seen to be intersecting at the abscissa of 1.425 on the x axis.

4. Smoker’s equation is convenient to use, in binary separations with
a) Large number of stages
b) Small number of stages
c) Independent stages
d) Dependent stages

Answer: a [Reason:] Smoker’s equation is convenient to use in binary separations with large number of stages, while Fenske’s for the minimum number of trays.

5. Smoker’s equation is based on assumption?
a) Constant molar overflow and volatility
b) Constant Molar overflow and viscosity
c) Constant feed and stages
d) Constant Pressure

Answer: a [Reason:] Smoker’s equation is based on assumption of Constant molar overflow and volatility, while McCabe and Ponchan are based on Constant molar overflow only.

6. If NR is 5.44 and NS is 3.42. Total stages are
a) 2.02
b) 1.8
c) 8.86
d) 1.59

Answer: c [Reason:] as NR + NS = 5.44 + 3.42 = 8.86.

7. According to smoker’s equation, b is given as
a) R+1
b) xD/R+1
c) xD/y
d) y/R+1

Answer: b [Reason:] According to smoker’s equation b is given as xD/R+1, where XD is the moles of liquid distilled with the rate of reflux R.

8. According to smoker’s equation, C is given as
a) 1 + (α -1) k
b) 1 -(α -1)k
c) 1 -(α +1)k
d) α -1

Answer: a [Reason:] According to smoker’s equation C is given as 1 + (α -1) k, where k value is calculated from bottom and top sections of the column.

9. Calculate b? If xD= 0.95 and R=8
a) 0.445
b) 0.118
c) 0.2375
d) 0.568

Answer: c [Reason:] AS xD/R+1 = 0.95/8+1= 0.2375.

10. If reflux ratio is 3, then slope m is estimated as
a) 0.75
b) 1
c) 0.66
d) 0.90

Answer: a [Reason:] As R/R+1 = 3/3+1 = 0.75.

## Set 4

1. A layer of packing above the liquid distributor is called?
a) Dry packing
b) Wet packing
c) Can packing
d) Trump packing

Answer: a [Reason:] A layer put above the liquid distributor is called dry packing, which acts as an entrainment eliminator, to remove the entrainment liquid droplets.

2. The Eckert chart contains a parameter FP which is called?
a) Pushing factor
b) Possibility factor
c) Praining factor
d) Packing factor

Answer: d [Reason:] A parameter P that characteristics the packing and is called as packing factor, originally introduced by Lobo in 1945, also represented as Cf.

3. The packing factor used to be taken as?
a) ap/e3
b) ap/e2
c) ap2/e2
d) ap3/e4

Answer: a [Reason:] The packing factor is taken as to be ap/e3, where ap= surface of the packing per unit volume and e = void fraction of the packed bed.

4. The difference between the total hold up and the static holdup is called?
a) Static holdup
b) Operating holdup
c) Dynamic holdup
d) Full holdup

Answer: b [Reason:] The difference between the total hold up and the static holdup is called Operating holdup and sometimes is also refereed as dynamic holdup.

5. The MWR stands for?
a) Maximum Working Rate
b) Mixed Working Rate
c) Minimum Wetting Rate
d) Mega Weeping Rate

Answer: a [Reason:] It is the liquid throughput below the film packing surface breaks up reducing the wetted area.

6. Liquid remaining in unit volume of bed after bed is drained is?
a) Final holdup
b) Total holdup
c) Static holdup
d) Full holdup

Answer: c [Reason:] It is the liquid remaining in unit volume of the bed after the bed is drained for a reasonable time, it is pretty small compared to total holdup.

7. Fs is denoted as?
a) Capacity parameter
b) Final storage
c) Full standup
d) Finishing Standup

Answer: a [Reason:] Plot of dP vs. Fs, it may be noted that quantity Fs is also taken as a measure when pg<<pl, it is desirable that the flooding point or pressure drop is determined by interpolation.

8. Minimum liquid rate for random packing is reported as?
a) 10-14 gpm/ft2
b) 8-10 gpm/ft2
c) 1-9 gpm/ft2
d) 0.5-2 gpm/ft2

Answer: d [Reason:] Minimum liquid rate for random packing is reported as 0.5-2 gpm/ft2 and for structured packing is 0.1-0.2 gpm/ft2.

9. The dry bed pressure drop can be calculated using?
a) Ergun’s Equation.
b) Fenske’s Equation
c) Bessel’s Equation
d) Barnaul’s Equation

Answer: a [Reason:] The Ergun’s equation can be used using the pressure drop calculation for all the packed towers and other equipment’s that use packings.

10. The quantity Cs is?
a) Capricorn Constant
b) Souder’s-Brown constant
c) Sider Tate equation
d) Chaperon Equation

Answer: b [Reason:] The quantity Cs is akin Souder’s-Brown constant, may be corrected for changes in interfacial tension and viscosity if necessary.

## Set 5

1. Light non-keys end up as a
a) Final product
b) Feed outlet
c) Bottom end product

Answer: d [Reason:] Light non-keys always end up as an overhead product, while heavy keys at bottom product of the column.

2. Heavy non-keys end up as a
a) Final product
b) Feed outlet
c) Bottom end product

Answer: c [Reason:] Heavy non-keys always end up as a Bottom end product, this occurs due to volatility difference in the components.

3. The reflux ratio corresponding to the minimum total cost is called as
a) Optimum reflux ratio
b) Minimum reflux ratio
c) Final Ratio
d) Total Reflux Ratio

Answer: a [Reason:] The reflux ratio corresponding to the minimum total cost is called as Optimum reflux ratio and the final cost related is called as final ratio.

4. The concentration of multi component mixture in mass transfer process, can be represented by
a) Mass concentration
b) Molar concentration
c) Molar density
d) Each quantity is important

Answer: d [Reason:] The concentration of multi component mixture can be represented by all molar forms independent of property, so concentration as well as density are equally important.

5. HETP is numerically equal to HTU, If and only if operating line
a) Lies below the equilibrium line
b) Lies above equilibrium line
c) At equilibrium line
d) Is far from equilibrium line

Answer: c [Reason:] HETP is numerically equal to HTU if and only if operating line is parallel to equilibrium line, this means NTU i.e. number of transfer units are unity.

6. In binary system, Separation is very efficient when relative volatility is
a) 1
b) >1
c) <1
d) Zero

Answer: b [Reason:] If α >1 efficiency of separation increases, if separation is difficult then α < 1 and if no separation is possible then α= 0.

7. In batch distillation, with constant reflux overhead product composition
a) Increases with time
b) Decreases with time
c) Does not vary with time
d) Does vary with time

Answer: b [Reason:] As batch operation feed reduces with given time thus reflux decreases, as batch distillation contains a limited amount of feed.

8. Which of the following assumes constant molal vaporization and overflow?
a) McCabe Thiele method
b) Ponchan Savarit Method
c) Enthalpy concentration method
d) Plate absorption method

Answer: a [Reason:] The McCabe Thiele method assumes constant molal vaporization and overflow, while the Ponchan Savarit Method is based on the enthalpy balance of components.

9. The McCabe Thiele method
a) Uses molal units for material and energy balance
b) Uses weight fractions to express liquid and vapor composition
c) Can use any type of units
d) Is more accurate than ponchan savarit method