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Correct choice is (a) Yes

Best explanation: Of course, a transducer is a device that has the capability to emit data as well as to ACCEPT. Transducer converts SIGNAL from ONE form of energy to ANOTHER.

Right choice is (a) The output of an encoder is a binary code for 1-of-N input

For EXPLANATION I WOULD say: An encoder is a combinational circuit ENCODING the information of 2^n input lines to n output lines, THUS producing the binary equivalent of the input. It performs the opposite operation of a decoder which results in 2^n outputs from n INPUTS. Thus, an encoder different from a decoder because of the output of an encoder is a binary code for 1-of-N input.

Right answer is (a) 4

Explanation: An encoder is a combinational circuit ENCODING the information of 2^n input LINES to n output lines, thus PRODUCING the binary equivalent of the input. Thus, a decimal to BCD encoder has 4 outputs.

Right OPTION is (a) The AC voltage applied between segment and a common ELEMENT

Easiest explanation: The ac voltage applied between the segment and a common element is CALLED the backplane(BP). In which each segment is driven by an EX-OR gate.

The correct answer is (c) 10

For explanation: An encoder is a combinational circuit ENCODING the information of 2^n input LINES to n output lines, thus PRODUCING the binary equivalent of the input. Thus, a DECIMAL-to-bcd converter has decimal values as inputs which range from 0-9. So, a total of 10 inputs are there in adecimal-to-BCD encoder.

The correct CHOICE is (B) 7

Explanation: There are 7 LEDs used in a 7 segment DISPLAY. 7 segment displays are used for displaying DECIMAL numerals which are comparatively convenient to dot MATRIX displays.

Right OPTION is (a) 3 to 15V

The best EXPLANATION: LCDs operate from a VOLTAGE ranges from 3 to 15V RMS. They provide thinner displays as compared to CATHODE Ray Tubes.

Correct choice is (c) 1960s

The best explanation: The first LCDS BECAME commercially available in the late 1960s and were based on a light-SCATTERING EFFECT known as the dynamic scattering mode.

The correct option is (a) the molecule’s chemical STRUCTURE

The best explanation: For LCDs, the change in optical properties results from orienting the molecular AXES either along or perpendicular to the APPLIED electric field, the preferred direction being determined by the DETAILS of the molecule’s chemical structure.

Correct ANSWER is (b) ELECTRIC field

To explain: In LCD, the electric field is induced by a small electric voltage applied across it; Due to which the orientation of molecules in a LAYER of liquid crystals can be changed.

The correct OPTION is (a) IC 74154

To EXPLAIN: IC 74154 is USED for the implementation of 1-to-16 DEMUX, whose output is inverted INPUT.

The correct choice is (c) Light

The BEST explanation: The optical properties of LIQUID crystals depend on the DIRECTION of light travels through a LAYER of the material.

Right answer is (b) SELECT inputs

To elaborate: A DEMULTIPLEXER SENDS a single input to multiple outputs, depending on the select lines. As the select input changes, the output of the multiplexer varies ACCORDING to that input.

Correct answer is (a) 2

For explanation I WOULD say: The formula for TOTAL no. of OUTPUTS is given by 2^n, where n is the no. of SELECT lines. Therefore, for 1:4 demultiplexer, 2 select lines are required.

The correct ANSWER is (b) Single INPUT, multiple outputs

Explanation: A DEMULTIPLEXER sends a single input to multiple outputs, depending on the select lines. Demultiplexer converts single input into multiple outputs.

Correct answer is (d) Y3

Easy explanation: It can be CALCULATED from the figure shown below:

For C0 =1 and C1 =0, Y3 will be the output as 0 and 1 are the bit combinations of 1.

Correct answer is (B) Y1

Best EXPLANATION: It can be calculated from the FIGURE shown below:

For C0 =1 and C1 =0, Y1 will be the OUTPUT as 0 and 1 are the bit combinations of 1.

The correct ANSWER is (b) Select inputs

The explanation: A DEMULTIPLEXER sends a single input to multiple outputs, DEPENDING on the select LINES. As the select input changes, the output of the multiplexer varies ACCORDING to that input.

Correct option is (a) The INPUT will be distributed to one of the outputs

The BEST explanation: A demultiplexer sends a SINGLE input to multiple outputs, DEPENDING on the select lines. For one input, the demultiplexer gives several outputs. That is why it is called a DATA distributor.

The correct option is (d) It can be used to route data and it is an application of multiplexer

To explain I would say: MULTIPLEXING MEANS passing more than ONE data through the same CHANNEL. Data routing is an application of multiplexer and it can be used to route data from one of SEVERAL source to destination.

Right option is (d) One into MANY as WELL as Distributor

Explanation: The word demultiplex means “one into many” and distributor. A demultiplexer sends a SINGLE input to MULTIPLE outputs, depending on the select lines. It is CLEAR from the diagram:

Right CHOICE is (a) Bidirectional

For explanation I would SAY: ONE multiplexer can be used as demultiplexer. HENCE, it is CALLED bidirectional or two-way transmission.

Correct choice is (c) Rotary switch

Explanation: A combinational CIRCUIT that selects ONE from many inputs is known as Multiplexer. A basic multiplexer principle can be demonstrated through the use of a rotary switch. Because rotary switch GIVES one OUTPUT corresponding to their inputs.

Correct answer is (d) SEVERAL SSI logic gates or combinational logic circuits

The EXPLANATION is: A combinational circuit that selects one from many INPUTS is known as Multiplexer. One multiplexer can take the place of several SSI logic gates or combinational logic circuits because it has a lot of functions to perform DIFFERENT operations.

The correct answer is (a) Multiplexer

Explanation: A combinational circuit that selects one from MANY inputs is known as Multiplexer. In multiplexer, DIFFERENT inputs are inserted parallely and then it GIVES one OUTPUT which is in serial form.

The correct choice is (a) INPUT combination at the time

To elaborate: A combinational circuit is one in which the OUTPUT DEPENDS on the input combination at the time, whereas, a sequential circuit is one in which the output depends on present input as WELL past outputs.

Right option is (d) MULTIPLEXER

The EXPLANATION: A COMBINATIONAL CIRCUIT that selects one from many inputs is known as Multiplexer. Whereas, a combinational circuit that DIVIDES one input into multiple outputs is known as Demultiplexer.

The correct choice is (a) 1 SELECT line

Explanation: The two input multiplexer would have N select lines in 2^n. THUS n =1. THEREFORE, it has 1 select line.

Correct choice is (c) Strobe

Easy explanation: The ENABLE INPUT is also KNOWN as strobe which is used to cascade two or more multiplexer ICS to construct a multiplexer with a larger number of inputs. Enable input activates the multiplexer to operate.

The CORRECT answer is (B) X1

Easy explanation: The OUTPUT will be X1, because c1 = 0 and c0 = 1 results into 1 which further results as X1. And rest of the AND gates GIVES output as 0.

The correct answer is (d) 3

The best I can explain: 2^n input LINES, n control lines and 1 output line available for MUX. Here, 8 input lines mean 2^3 INPUTS. So, 3 control lines are possible. Depending on the STATUS of the select lines, the input is selected and FED to the output.

Correct option is (c) Rotary switch

The explanation: A basic MULTIPLEXER principle can be DEMONSTRATED through the use of a rotary switch. Since its behaviour is similar to the multiplexer. There are around 10 DIGITS out of which one is selected one at a time and fed to the OUTPUT.

The correct choice is (b) m

The explanation: If the NUMBER of N SELECTED input LINES is EQUAL to 2^m then it requires m select lines to select one of m select lines.

Right choice is (b) SELECTED LINES

For explanation I would say: The SELECTION of a particular input line is controlled by a set of selected lines in a multiplexer, which helps to select a particular input from SEVERAL sources.

Right answer is (a) One digital INFORMATION from several sources and transmits the selected one

The explanation: A digital multiplexer is a combinational circuit that SELECTS one digital information from several sources and transmits the selected information on a single output LINE depending on the status of the SELECT lines. That is why it is also known as a data SELECTOR.

Right answer is (d) Several SSI logic GATES or combinational logic circuits

For explanation: A multiplexer (or MUX) is a device that selects one of several analog or digital input signals and forwards the SELECTED input into a single line, DEPENDING on the active select LINES. Since many operational behaviour can be PERFORMED by using a multiplexer. Whereas, a combinational circuit is a combination of many logic gates which makes the circuit more complex.

The correct CHOICE is (c) To ACTIVE the entire chip

The best explanation: Enable input is used to active the chip, when enable is HIGH the chip works (ACTIVE), when enable is LOW the chip does not work (MEMORY). However, Enable can be Active-High or Active-Low, indicating it is active either when it is connected to VCC or GND respectively.

Right OPTION is (a) Inputs

To elaborate: It is possible for an enable or STROBE input to UNDERGO an expansion of two or more MUX ICs to the DIGITAL multiplexer with the PROFICIENCY of large number of inputs.