Grinding is known to produce residual stresses on the finished surface. These residual stresses play an important role in determining the life of the component in many applications. What type of residual stresses are desirable to reduce the risk of failure due to surface cracks?

a. Compressive
b. Tensile
c. Both are disadvantageous
d. Both tensile and compressive are advantageous

Apiston-cylinder with a volume of 0.25 m3 holds 1 kg of air (r 0.287 k/kgk) at a temperature of 100 c. heat transfer to the cylinder causes an isothermal expansion of the piston until the volume triples. how much heat is added to the piston-cylinder?

Describe one experiment in which the glass transition temperature and melting temperature of a totally amorphous thermoplastic material can be determined. show the relevant experimental results in a diagram which should be properly annotated with the two temperatures clearly marked. what is likely to happen to the curve in the diagram if the amorphous polymer is replaced by a thermosetting type?

Air inially occupying a volume of 1 m2 at 100 kpa, 27 c undergoes three internally reversible processes in series. process 1-2 compression to 500 kpa during which pv constant process 2-3 adiabatic expanslon to 100 kpa process 3-1: constant-pressure expansion to 100 kpa (a) calculate the change of entropy for each of the three processes. (b) calculate the heat and work involved in each process. (c) is this cycle a power cycle or refrigeration cycle?