The northbound approach of a signalized intersection has a downgrade of 3% (i. e., g=-0.03). the design approach speed is 45 mph. what is the recommended yellow time to the next 0.1 second? (b) if the width of the cross street (in the east-west direction) is 58 ft and the design vehicle length is 16 ft, what is the recommended all-red time to the next 0.1 second. (c) pedestrians are crossing the east-west street. the crosswalk that is marked to guide pedestrians walking in the north-south direction has a width of 10 ft. the design pedestrian volume is 22 persons/cycle. what is minimum time that should be set aside for pedestrians to cross?

Refrigerant 134a enters an insulated compressor operating at steady state as saturated vapor at -26°c with a volumetric flow rate of 0.18 m3/s. refrigerant exits at 9 bar, 70°c. changes in kinetic and potential energy from inlet to exit can be ignored. determine the volumetric flow rate at the exit, in m3/s, and the compressor power, in kw.

Air is to be cooled in the evaporator section of a refrigerator by passing it over a bank of 0.8-cm-outer-diameter and 0.4-m-long tubes inside which the refrigerant is evaporating at -20°c. air approaches the tube bank in the normal direction at 0°c and 1 atm with a mean velocity of 4 m/s. the tubes are arranged in-line with longitudinal and transverse pitches of sl- st 1.5 cm. there are 30 rows in the flow direction with 15 tubes in each row. determine (a) the refrigeration capacity of this system and (b) pressure drop across the tube bank. evaluate the air properties at an assumed mean temperature of -5°c and 1 atm. is this a good assumption?

Assuming compressible flow of air and that the measurements are done at flagstaff a pitot static tube that gives the difference of total and static pressure measures 0.35 m of mercury. what is the velocity of air? assume the temperature to be 300k. (submit your excel or matlab calculation sheet)