Consider a clay layer that is 1 m thick. The clay has a compression index of 0.35, a swell index of 0.07, a permeability of 4 x 10-7 cm/sec, a preconsolidation pressure of 172 kPa and a coefficient of consolidation of 2.7 x 10-4 cmimin The initial effective stress at the midpoint of the layer is 140 kPa, and the soil has a void ratio of 1.01. The stress is increased to 200 kPa. The soil is drained above and below. The total primary consolidation expected is 4.40 cm. How much time in days is required for 2.0 cm of primary settlement to occur?

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?

Afluid flows with a velocity field given by v=(x/t)i.. determine the local and convective accelerations when x=3 and t=1.

Shafts are machine elements that are used to a) carry axial loads b) direct shear loads c) transmit power d) rotate at constant speed e) none of the above circular and square shafts subjected to the same torque under the same circum behave a) the same way b) almost the same way