Coursera Quiz

1 . A piezoelectric accelerometer has a damping ratio of 0.65, a proof mass of 0.5 grams, and a spring rate of 10,000 N/mm. What is the damped natural frequency in hz of this device? (Type in an integer) Hint: Make sure your units of measure are consistent first, then use the formulae to calculate the natural and damped natural frequencies. 17104 2. A series RLC circuit has a resistance of 6.0 ohm, a capacitance of 5882 microfarads, and an inductance of 100 millihenries. What is the x location in rad/sec of the pole s1 ? (Type in a one-decimal number, make sure to use the – sign for a negative integer) Hint: Make sure your units of measure are consistent first, then use the formulae to calculate the natural and damped natural frequencies, as well as the damping ratio. 3.A series RLC circuit has a resistance of resistance of 6.0 ohm, a capacitance of 5882 microfarads, and an inductance of 100 millihenries. What is the y location in rad/sec of the pole s1. (Type ...

Motor and Motor Control Circuits Course Project 2 Quiz Answers Coursera 1. What is true about the digital pulse trains of the EN11 rotary switch? They are out of phase as the switch rotates.The phase difference tells you the direction of rotation, and the number of edges counted tells you the angular position 2. Refer to our video on the rotary switch lab. When viewing the traces on the scope, how do you know which way the switch is rotating? 3. For the PSoC chip what is the minimum voltage level (in volts) that can be considered logic one? Type in a one decimal place number. 3.5 4. You are using the QuadDec internal device on the the PSOC chip in order to perform quadrature decoding for our "Rotary sensor lab". Suppose you rotate the rotary switch from on to off. You start in the on position and you rotate the switch from on to off and back at a frequency of 5 hz. If you set your clock frequency to 2 hz, what logical level will you measure to time t = 0.20 seconds? Type in a...

Motor and Motor Control Circuits Course Project 1 Quiz Answers ....Refer to our video lab on specifying a DC motor speed measurement. How does an FET work? Comment your answer below .... Refer to our video lab on specifying a DC motor speed measurement. How do you measure back EMF directly? It is not possible to measure the back EMF directly ....Refer to our video lab on specifying a DC motor speed measurement. Sup. pose the motor resistance is 2 ohms, motor inductance is 5 milli-henries, external voltage is 5 volts, and the back EMF time constant is .009 per RPM. As the motor accelerates, what is the motor current in milliamps at time t = 20 milliseconds when the motor is running at 500 RPM. Ignore any oscillation of the back EMF voltage due to commutation. Type an integer value of milli-amps. 250 ....Refer to our video lab on specifying a DC motor speed measurement. Why does the frequency of ripples in the de caying DC current signal increase as the motor speeds up? Select all that a...

Motor and Motor Control Circuits Week 4 Quiz Answers 1. In the video on "Illustrative example of a stepper motor drive" we showed you a stepper motor that rotated 90 degrees clockwise. How would you alter the sequence of energizing and de-energizing the coils in the first step to make the stepper motor run counter-clockwise? De-energize Phase 1 and energize Phase 2 South North 2. What is the definition of a phase in a stepper motor? A pair of windings on opposite sides of the rotor, one magnetic North and the other magnetized South 3. Which of the following are disadvantages of using a stepper motor relative to a DC motor? Select all that apply. You need to purchase motor driver circuitry, or design your own and write custom firmware 4. What happens if you provide double the rated voltage to a stepper motor? The speed and torque both increase, but by less than double 5. Which statement below correctly describes the difference between a unipolar drive and a bipolar drive for a...

Motor and Motor Control Circuits Week 3 Coursera Quiz Answers 1. What causes a motor to generate back emf? The armature windings rotate through the magnetic field created by the field windings. They then become a generator, creating a current in the opposite direction to the applied current 2. What is the power in horsepower of a DC motor operating at 1000 RPM and 2 lb-ft torque? (Type in a two-decimal number.) 0.38 3. Which of the following are causes of energy loss in a DC motor? Select all that apply. Current flow in the armature and field windings Magnetic hysteresis in the iron core Eddy current losses in the field windings 4. What is true about the speed of a shunt wound DC motor? Select all that apply. The speed is proportional to the square of the armature resistance The speed is inversely proportional to the magnetic flux 6. What is true about a permanent magnet DC motor? Items (1), (2), and (4) 7. Where might the motor control circuitry be located in a servomotor? In a separa...

 Week 5, Pressure, Force, Motion and Humidity Quiz Answers Coursera

 Week 4, Pressure, Force, Motion and Humidity Quiz Answers Coursera