When designing an opto-coupler circuit for a CNC machine, the micro-controller much be able to interface with the opto-coupler in the limit stop when the bed has reached its extreme x-axis limit. Which of the following is true for the sensor and the micro-controller interface? A. None of the above as the sensor does not work with micro-controllers.
B. The output of the photo-transistor in the opto-coupler circuk can be directly connected to the micro-controllers input pin
C. A opto-coupler drar needs a smoothing cult before it can be interfaced with a mer oder due to the fact that the oplo-coupler le analog controller reasonal
D. The microcontroller cant interface with the phototransistor opto-coupler eroult since i analog and the more controller is digital

Steam enters a converging nozzle at 3.0 mpa and 500°c with a at 1.8 mpa. for a nozzle exit area of 32 cm2, determine the exit velocity, mass flow rate, and exit mach number if the nozzle: negligible velocity, and it exits (a) is isentropic (b) has an efficiency of 94 percent

Acommercial grade cubical freezer, 4 m on a side, has a composite wall consisting of an exterior sheet of 5.0-mm thick plain carbon steel (kst= 60.5 w/m k), an intermediate layer of 100-mm thick polyurethane insulation (kins 0.02 w/m k), and an inner sheet of 5.0- mm thick aluminium alloy (kal polyurethane insulation and both metallic sheets are each characterized by a thermal contact resistance of r 2.5 x 104 m2 k/w. (a) what is the steady-state cooling load that must be maintained by the refrigerator under conditions for which the outer and inner surface temperatures are 25°c and -5°c, respectively? (b) for power saving purpose, which wall material should be increased/reduced in. thickness in order to reduce 50% of the cooling load found in part (a)? redesign the thickness of the proposed material. 177 w/m-k). adhesive interfaces between the q=575.93 w

Which one of the following faults cause the coffee in a brewer to keep boiling after the brewing cycle is finished? a. an open circuit in the heating element b. a short circuit at the terminals c. welded contacts on the thermostat d. a leak around the gasket