For a lead–tin alloy of composition 80 wt% sn–20 wt% pb and at 180°c (355°f) ,

(a) determine the mass fractions of the α and β phases.
(b) determine the mass fractions of primary β andeutectic microconstituents.
(c) determine the mass fraction of eutectic β.

Aturning operation is performed with following conditions: rake angle of 12°, a feed of 0.35 mm/rev, and a depth of cut of 1.1 mm. the work piece is aluminum alloy 6061 with t6 heat treatment (a16061-t6). the resultant chip thickness was measured to be 1.0 mm. estimate the cutting force, fc. use shear stress of 207 mpa and coefficient of friction on the tool face of 0.6.

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg. a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg.m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?

Ahousehold refrigerator operating steadily and with a coefficient of performance of 2.5 removes energy from a refrigerated space at a rate of 650 kj/h. evaluating electricity at $0.06 per kw.h, determine the cost of electricity in a month when the refrigerator operates for 360 hours.