MAE334FE_02_AnswerKey.doc - December 12, 2001- Page 1 Figure 1. Ideal Filter Characteristics Use the following answer for the next 4 questions a) high pass filter b) low pass filter c) notch filter d) band pass filter 1) Figure 1 (a) characterizes an ideal 2) Figure 1 (b) characterizes an ideal 3) Figure 1 (c) characterizes an ideal 4) Figure 1 (d) characterizes an idealMAE334FE_02_AnswerKey.doc - December 12, 2001- Page 2 Figure 2. Single Pole Passive Filter Circuit 5) The single pole passive filter drawn in Figure 2 is a a) low pass filter b) high pass filter c) band pass filter d) notch filter 6) The single pole passive filter drawn in Figure 2 has a cutoff frequency of a) fc=RC b) fc=1/RC c) fc=2π/RC d) fc=1/2πRC 7) The output, y(t), from the single pole passive filter in Figure 2 will a) always lag a dynamic input signal F(t). b) slightly amplify the input signal F(t). c) have a phase lag of 90 degrees at the cutoff frequency. 8) What would the time constant of a single pole Butterworth low pass filter built with a 1000 ohm resistor, R, and a 100 uF capacitor, C, be? a) 2πRC seconds b) 1/2πRC seconds c) 10-1 seconds = τ = RC = 1000 * 100 * 10-6 d) 1 seconds e) 105 seconds 9) Which low pass filter type has the steepest magnitude ratio roll off? a) Bessel b) Butterworth c) Chebyshev d) Elliptic F(t) y(t) R CMAE334FE_02_AnswerKey.doc - December 12, 2001- Page 3 10) Which low pass filter type has a linear phase shift? a) Bessel b) Butterworth c) Chebyshev d) Elliptic 11) The transfer function of the low pass filter tested in lab 5 is a complex valued function? a) true b) false 12) Both the magnitude ratio and phase lag vs. frequency can be obtained using the sine wave sweep method of determining the transfer function a) true b) false 13) At the filter cutoff frequency a 4 pole passive Butterworth low pass filter will attenuate the input signal a) -3 dB b) -4 dB c) -12 dB d) None of the above Figure 3. The equivalent circuit of an ideal operational amplifier. 14) For the ideal operational amplifier in Figure 3 a) rin = 0, ro = ∞, Avo = ∞ b) rin = 0, ro = 0, Avo = ∞ c) rin = ∞, ro = ∞, Avo = ∞ d) rin = ∞, ro = 0, Avo = ∞ e) rin = ∞, ro = 0, Avo = 1MAE334FE_02_AnswerKey.doc - December 12, 2001- Page 4 15) For the ideal operational amplifier in Figure 3 the bandwidth is not assumed to be infinite. a) true b) false 16) For the ideal operational amplifier in Figure 3 the output is zero if the input is zero. a) true b) false Figure 4. Basic Operational Amplifier Circuit 1 17) The basic operational amplifier circuit in Figure 4 is a) an inverting amplifier b) an integrating amplifier c) a differentiating amplifier d) a non-inverting amplifier 18) For the basic operational amplifier circuit in Figure 4, a) Iin = If, Ein = Es, Is = 0, Gain = -Rf/Rin b) Iin = If, Ein = IinRin, Gain = Rf/Rin c) Iin ≠ If, Es = 0, Is = 0, Gain = -Rf/Rin d) Iin = Ein/Rin, Es = 0, Is = 0, Gain = -Rf/Rin Use the following answers for the next 5 questions a) Integrator b) Non-inverting Amplifier c) Differential Amplifier d) Differentiator e) Inverting AmplifierMAE334FE_02_AnswerKey.doc - December 12, 2001- Page 5 Figure 5. Op-Amp Circuit 19) Figure 5 is a inverting amplifier (note that Ei is attached to the negative input) Figure 6. Op-Amp Circuit 20) Figure 6 is a differential amplifier Figure 7. Op-Amp Circuit 21) Figure 7 is an integratorMAE334FE_02_AnswerKey.doc - December 12, 2001- Page 6 Figure 8. Op-Amp Circuit 22) Figure 8 is a differentiator Figure 9. Op-Amp Circuit 23) Figure 9 is a inverting amplifier 24) The gain of the amplifier circuit in Figure 9 is a) -R1R2 b) -R1/R2 c) R1R2 d) R2/R1 e) -R2/R1 25) To avoid voltage measurement loading errors the input resistance of the measuring meter a) should be about the same as the sensor output resistance. b) should be much less than the sensor output resistance. c) should be much greater than the sensor output resistance. 26) For flow variables, the input impedance of the measurement instrument should be much greater than the output impedance of the sensor. a) true b) falseMAE334FE_02_AnswerKey.doc - December 12, 2001- Page 7 27) Temperature is a) an effort variable b) a flow variable 28) Temperature should be measured with a high input impedance sensor. a) true b) false 29) Heat Flux is a) an effort variable b) a flow variable 30) Heat flux should be measured with a high input impedance sensor. a) true b) false 31) If you would like to resolve the daily, weekly, monthly and summer seasonal (June 21st to September 21st) temperature fluctuations at your summer home what is the least amount of data you must collect? a) once a day for one week b) once a day for 3 months c) twice a day for 6 months d) twice a day for 3 months e) ten times a day for 3 months 32) If you need to present a reasonable graph of the temperature fluctuations in the previous question (31) what is the least amount of data you must collect? a) 4 times a day for 6 months b) 10 times a day for one and a half months c) 30 times a day for 3 months d) 10 times a day for 3 months e) twice a day for 3 months 33) Given the ADC hardware and thermocouple used in lab 2 this semester, what is the highest frequency air temperature fluctuation you could accurately track? a) approximately 1 Hz. b) approximately 45 Hz. c) approximately 0.1 Hz. d) approximately 0.001 Hz., ττττ ≈ minutes, therefore maximum tracking frequency is 1/minutesMAE334FE_02_AnswerKey.doc - December 12, 2001- Page 8 34) Given the ADC and thermocouple hardware used in the lab this semester to regulate your spa water temperature. How small of a temperature change would you be able to detect assuming there was no electronic noise. (The ADC full scale range is 10 volts, the maximum gain is 100 and the thermocouple static sensitivity is 25,000 degrees C/Volt) a) approximately 6 degrees C b) approximately 1 degree C = 10/100/4096*25,000 = 0.6 degrees c) approximately 60 degrees C d) approximately 0.04 degree C e) None of the above (will be accepted) 35) The binary representation of 5 is: a) 0101 b) 1010 c) 0110 d) 1100 e) None of the above 36) The 4 bit 2’s complement representation of -2 is: a) 1000 b) 0010 c) 1111 d) 1110 e) None of the above 37) The time constant, τ, of the thermocouple response plotted in Figure 10 is approximately: a) 5 seconds b) 10 seconds c) 15