. Refrigerant-134a enters the coils of the evaporator of a refrigeration system as a saturated liquid– vapor mixture at a pressure of 160 kPa. The refrigerant absorbs 180 kJ of heat from the cooled
space, which is maintained at -5°C, and leaves as saturated vapor at the same pressure. Determine
(a) the entropy change of the refrigerant, (b) the entropy change of the cooled space, and (c) the
total entropy change for this process.

20. threshold braking in the vehicle's braking system occurs when a. the brake pedal is pushed, heel on floorboard, with full foot pressure. b. the brakes are exerting full braking power, without traction loss. c. the driver begins pushing down the brake pedal, with moderate slowdown. d. the brakes just begin to take hold with a gradual slowdown.

Explain the comparisons between nature and packingtown that appears on pages 81 and 82 answer

An electron is trapped at a defect in a crystal. the defect may be modeled as a one-dimensional, rigid-walled box of width 1.00 nm. (a) sketch the wavefunctions and probability densities for the n 1 and n 2 states. (b) for the n 1 state, nd the probability of nding the electron between x1 0.15 nm and x2 0.35 nm, where x 0 is the left side of the box. (c) repeat (b) for the n 2 state. (d) calculate the energies in electron volts of the n 1 and n 2 states