Low Pass Filter Question & AnswersFebruary 28, 2022 By WatElectronics This article lists 100 Low Pass Filter (LPF) MCQs for engineering students. All the Low Pass Filter (LPF) Questions & Answers given below include a hint and a link wherever possible to the relevant topic. This is helpful for users who are preparing for their exams, interviews, or professionals who would like to brush up their fundamentals on Low Pass Filter (LPF).A filter is an electronic passive device designed to obstruct a few frequencies and allow the required frequency. They are classified into 4 types namely low pass filter, high pass filter, bandpass filter, and band rejected filter. A low pass filter is a device that permits only the lower frequency value signal and blocks high-frequency value signals from it. They are classified into 2 types namely Inductive and capacitive. These filters are designed using 3 main passive components such as a resistor, capacitor, and inductor.LPF can be designed with first order and second order LPF filters wherein first-order LPF only one set of RC circuits is connected with the source and in second-order LPF multiple RC circuits are cascaded. The gain obtained from first-order LPF is about 0.707A. They provide benefits in terms of eliminating the aliasing effect, minimum output impedance, protecting cut-off frequency, etc. The minimum voltage gain value they limit is below one. These filters are deployed in equalizers, speakers, amplifiers, etc.1). The input frequency applied to low pass filter is ____? High Low Zero Constant HintFL frequency component means?2). The output frequency obtained from low pass filter is ____? High Low Zero Constant HintFH frequency component means?3). A device that separates disturbances from a signal is ____? Filter Diode Switch All the above HintExtracts important frequencies from signals.4). Which of the following are the applications of filter? Radar TV Control systems All the above HintHome appliances.5). Which of the following are the types of filters? Linear and non-linear Active, passive Analog, digital All the above HintMultiple types.6). _____ parameter of a filter depends on design of filter? Frequency response Voltage Breakdown value All the above HintMeasures in terms of Hertz.7). A LPF is also called ____? High cut filter Treble-cut filter Low-cut filter Both a and b Hint2 names.8). Which of the following are LPF circuits? Hiss filter Anti-aliasing Digital All the above Hint3 types.9). Which of the following is the application of hiss filter? Audio ADC Image blur All the above HintVoice message.10). Which of the following is the application of anti-aliasing filter? Audio ADC Image blur All the above HintConverter.11). Which of the following is the application of digital filter? Audio ADC Image blur All the above HintViedo application. Read more about Control Systems.12). A proto-type filter is a _____ filter? Electronic Mechanic Chemical Bio HintA discrete device.13). Which of the following are the types of proto-type filter? LPF BPF BSF All the above Hint3 examples.14). Which of the following are the applications of hiss filter? Acoustics Optics Electronics All the above Hint3 applications.15). Which of the following is the low frequency value? 100 KHz <100KHz >100KHz =1000KHz HintLower value.16). Which of the following is the high frequency value? 100 KHz <100KHz >100KHz =1000KHz HintGreater value.17). Which of the following is the output wave shape obtained from ideal low pass filter? Sine Rectangle Triangle Peak HintArea = a*b.18). Which of the following are the components of low frequency type a passive filters? Resistors Capacitors Inductors Both a and b Hint3 components.19). Which of the following are the components of high frequency type passive filters? Resistors Capacitors Inductors All the above Hint3 types.20). A circuit design with resistor, capacitor and inductor component is called _____circuit? RLC RC LC RL Hint3 components.21). A first order LPF filter is called ____ circuit? Integrator Differentiator Multiplier Adder HintA circuit that produces a steadily changing output voltage for a constant input voltage.22). The components of LPF are connected in _____ configuration? Series Parallel Concurrent Both b and c HintOne after the other connection.23). Increase in frequency of LPF _____ the gain value? Increases Decreases Zero Constant HintInversely proportional.24). The gain in transition band end stage of a LPF is ____? 1 0 Infinity Constant HintLeast value.25). The BW of LPF is ____? High Low Zero Limited HintSpecific range.Low Pass Filter Interview Questions and Answers26). At which of the following component of LPF input is applied? Resistor Capacitor Inductor Load HintMeasures in ohms.27). At which of the following component of LPF output is obtained? Resistor Capacitor Inductor Load HintMeasures in Farads.28). A capacitor has ___ number of parallel plates? 1 2 3 4 HintEven number.29). An LPF first order filter are classified in to ___ number of types? 1 2 3 4 HintEven number.30). Which of the following are the components of LPF inductive type circuit? Resistor Inductor Capacitor Both a and b Hint2 components.31). Which of the following are the components of LPF capacitive type circuit? Resistor Inductor Capacitor Both a and c Hint2 components.32). Increase in input frequency of LPF inductive type circuit ____ the value of inductors impedance? Increases Decreases Zero Constant HintDirectly proportional.33). Which of the following is the advantage of Inductive based LPF? Blocks high frequency Allows low frequency Generates constant frequency Both a and b Hint2 advantages.34). A capacitive type LPF is also called ___? Simple LPF Dual LPF Harmonic LPF All the above HintNamed by its design.35). Increases in input signal ____ the impedance of capacitor? Increases Decreases Zero Infinity HintInversely proportional.36). Which of the following are the components of second order LPF? Resistor Capacitor Inductor All the above HintPassive components.37). The output from second order LPF is taken from ___ component? Resistor Capacitor Inductor All the above HintParallel plate device.38). Which of the following are passive components in second order LPF responsible for blocking high frequency? Resistor Capacitor Inductor Both b and c Hint2 components.39). A LPF designed with an OP-amp is ____ type of LPF? Active Passive Zero Both a and b HintSource-independent device.40). Which of the following is the function of op-amp in op-amp LPF? Signal amplification Gain control Noise free Both a and b Hint2 functions.41). An OP-amp LPF has _____ input impedance? High Low Zero Constant HintCondition where current flow is opposed.42). An OP-amp LPF has _____ output impedance? High Low Zero Constant HintCurrent flow is high.43). An op-amp LPF has _____ noise? High Low Zero Constant HintHigher signal efficiency.44). An op-amp LPF has _____ performance level? High Low Zero Constant HintGood efficiency.45). Op-amp in op-amp LPF is connected to ___ components terminal? Resistors Capacitors Inductors Both b and c Hint2 parallel plates device.46). An op-amp poses ____ type of characteristics? Linear Non-linear Zero Constant HintEqual input and output wave.47). An op-amp has ___ number of terminals? 2 3 4 5 HintOdd number.48). An inverted terminal in op-amp is called ____? Positive Negative Zero Both b and c HintInverted polarity.49). An non-inverted terminal in op-amp is called ____? Positive Negative Zero Both b and c HintHoles carriers polarity.50). The output amplitude obtained from RC low pass is _____ the amplitude of input signal in first order op-amp LPF? Large Small Zero Infinity HintOutput inversely proportional to input.Low Pass Filter Quiz Questions and Answers.51). The power gain of LPF op-amp is ____ in first order op-amp LPF? Large Small Zero Infinity HintGreater efficiency.52). The stability of LPF op-amp is ____ in first order op-amp LPF? Large Small Zero Infinity HintGreater efficiency.53). OP-amp with LPF acts as___ circuit? Buffer Voltage follower Current follower Both a and b Hint2 application. Read more about Voltage Follower.54). The DC gain of OP-amp with LPF is ____ in first order op-amp LPF? =1 >1 <1 0 HintSingle value.55). At which frequency value, RC circuit signal flow via op-amp for amplification in first order op-amp LPF? Low High Zero Constant HintFL frequency component means?56). Which of the following is voltage gain of first order op-amp LPF? 1/R1+R2 R1+R2 1/R1-R2 R1* R2 HintRatio of terms.57). How many RC filters are cascaded in second order LPF? 1 2 3 4 HintEven number.58). Op-amp in second order LPF acts as ___? Voltage controlled source amplifier Current controlled source amplifier Resistance controlled source amplifier Capacitance controlled source amplifier HintA source the output voltage or current is controlled by the input voltage.59). The band gain of second order LPF is ____ times the first order LPF? 2 3 4 5 HintEven number.60). Which of the following is the value of second order active LPF op-amp band gain? 40 dB/decade 50 dB/decade 60 dB/decade 70 dB/decade Hint20*2=?61). Cascading of multiple filter circuits is ____ order type filter? High Low Constant Zero HintMaximum value.62). Which of the following is the gain value of first order LPF active filter at cut-off frequency? -3dB -4dB -5dB -6dB HintOdd value.63). Which of the following is the gain value of second order LPF active filter at cut-off frequency? -3dB -4dB -5dB -6dB Hint2*3=?64). The value of gain of first order filter is ___ times the second order LPF gain? 2 3 4 5 HintEven number.65). Which of the following is the formula of gain of second order active LPF? Av1*Av2 Av1+Av2 Av1-Av2 Av1/Av2 HintProduct of terms.66). Which of the following is the formula of total gain of second order active LPF? Av1*Av2 Av1+Av2 Av1-Av2 Av1/Av2 HintSum of terms.67). Gain is expressed in terms of ___ units? dB Hertz Baud rate Both b and c HintRepresented as 10log(Poutput / Pinput).68). A LPF calculator is used for calculating ____ LPF circuit parameters? Cut-off frequency Voltage gain Phase shift All the above Hint3 parameters.69). Which of the following is the transfer function equation of second order LPF filter? H(s)=Vo(s)/Vi(s) H(s)=Vi(s)/Vo(s) H(s)=1/(1+sCR) Both a and c HintRatio and sum of terms.70). Which of the formula of ‘s’ in transfer function? jw j/w w/j w-j HintProduct of terms.71). The value of transfer function of second order LPF filter when w=0 is_________? 1 0 Constant Infinity HintLeast value.72). Which of the following is the value of transfer function of second order LPF filter when w=1/CR? 0.707 0 0.1 0.5 HintOdd value.73). Which of the following is the value of transfer function of second order LPF filter when w=infinity? 0.707 0 0.1 0.5 HintLeast value.74). Which of the following is the gain of transfer function of second order LPF filter in frequency domain? 1/sqt[1+(w/wc)^2] 1/[1+(w/wc)^2] 1/sqt[1-(w/wc)^2] 1/sqt[1+(w/wc)^3] HintSum and square root formula.75). Which of the following is the total gain of transfer function of second order LPF filter in frequency domain? 20log10(Vout/Vin) 20log10(Vin/Vout) 20log10(Vout+Vin) 20log10(Vout-Vin) HintRatio of terms.Low Pass Filter MCQs for Exams76). Which of the following is the phase shift formula of LPF? tan-1 [w/wc] Sin-1[w/wc] Cos [w/wc] Tan[w/wc] HintInverse function.77). Which of the following is the cut off frequency of LPF? 1/2πRC 2πRC 1/πRC 1/4πRC HintLeast value.78). Which of the following is the phase shift formula in RC format of LPF? tan-1[2 πRC] tan-1[1/2 πRC] tan-1[1/ πRC] tan-1[1-2 πRC] HintProduct of terms.79). Which of the following is the capacitive reactance formula of LPF? 1/2 πRC 1-2 πRC 1+2 πRC 1/ πRC HintRatio of terms.80). Frequency is expressed in terms of ___ units? Hertz Volts Amperes Henry HintDefined as one cycle per second.81). Increase in frequency of LPF, the output voltage _____ the input voltage? <70% >70% =70% Both a and b HintLower value.82). A device that measures amplitude of a frequency component is ____? Wave analyzer Signal analyzer Carrier frequency voltmeter All the above Hint3 names. Read more Wave Analyser83). Which of the following is the frequency of wave analyzer? 50MHz 10MHZ 100MHz 110MHz HintMinimum value.84). Which off the following are the components of wave analyzer? LPF Primary detector Full wave rectifier All the above Hint3 components. Read more about Full Wave Rectifier.85). A device that increases the amplitude of a signal is called ___? Amplifier Rectifier Tuner Oscillator HintA electronic device that can increase the power of a signal.86). Which of the following are the major component amplifiers? FET BJT CMOS Both a and b Hint2 components.87). FET stands for ___? Field Effect Transistor Fine Effect Transistor Field Elevate Transistor Field Effect Type HintA transistor that uses an electric field to control the flow of current in a semiconductor. Read more about FET.88). A BJT has ___ number of terminals? 1 2 3 4 HintOdd value.89). A DC value current is ____ dimensional? 1D 2D 3D 4D HintSingle co-ordinate.90). A DC value flows through which of the following substances? Conductor Insulators Semiconductor All the above Hint3 substances.91). The characteristics of a LPF are plotted on _____ dimension? 1 2 3 4 HintX and Y coordinates.92). Which of the following parameter of LPF characteristics is plotted on X-axis? Gain Angular frequency Voltage Current HintHorizontal axis.93). Which of the following parameter of LPF characteristics is plotted on Y-axis? Gain Angular frequency Voltage Current HintMeasure of the ability of a two-port circuit (often an amplifier) to increase the power or amplitude of a signal from the input to output.94). A cut-off frequency is also called ____? Corner frequency Break frequency Highest frequency Both a and b Hint2 names.95). A bandwidth consists of which of the following frequencies? Higher frequency Lower frequency Mid frequency All the above Hint3 types of frequencies.96). A frequency response of a signal is a measurement of ____ ? System spectrum System input Characteristic Both a and b Hint2 types.97). ____ type of filter can be used as audio and feedback systems? Analog Digital Both a and b None of the above Hint0's and 1's representation.98). A resistor has ___ number of terminals? 1 2 3 4 HintEven number.99). Which of the following is the function of a resistor? Minimize current flow Remove transmission lines Bias active elements All the above Hint3 functions.100). Resistors are elements of ____? Electrical networks Electronic circuits Mechanical devices Both a and b Hint2 elements. Please fill in the comment box below. Time is Up! Time's up