An escalator handles a steady load of 26 people per minute in elevating them from the first to the second floor through a vertical rise of 27.5 ft. The average person weighs 124 lb. If the motor which drives the unit delivers 3.8 hp, calculate the mechanical efficiency e of the system.

For the closed feedwater heater below, feedwater enters state 3 at a pressure of 2000 psia and temperature of 420 °f at a rate of ix10 ibhr. the feedwat extracted steam enters state 1 at a pressure of 1000 psia and enthalpy of 1500 btu/lbm. the extracted er leaves at an enthalpy of 528.7 btu/lbm steam leaves as a saturated liquid. (16) a) determine the mass flow rate of the extraction steam used to heat the feedwater (10) b) determine the terminal temperature difference of the closed feedwater heater

The sum of the normal stresses does not change as the stress state rotates through an angle. a)-trune b)- false

What is the chief metrological difference between measuring with a microscope and with an electronic comparator? a. the microscope is limited to small workpieces.a. the microscope is limited to small workpieces. c. the comparator can only examine one point on the workpiece. d. the microscope carries its own standard.