The 50-Ib crate shown in figure below is acted upon by a force having a variable magnitude p=(20t) Ib, where t is in seconds. Determine the crates velocity 2s after p has been applied. the initial velocity is v1=3ft/s down the plane, and the coefficient of kinetic friction between the crate and the plane is uk=0.3.

Slip occurs via two partial dislocations because of (a) the shorter path of the partial dislocation lines; (b) the lower energy state through partial dislocations; (c) the charge balance.

Analyze the factors that influence the choice between the following pairs of processes to make the products indicated: i) sand casting versus die casting of an electric-motor housing ii) thread rolling versus machining of a bolt for high-strength application. (co3/c5)

Determine the time of the day and month of the year at which the peak sensible cooling load occurs for a top floor, north-eastern corner room of an office building in durban for the following conditions: floor area: 8 x 8 x 3 m east and north walls: 115 mm face brick (outside), 20 mm air space, 115 mm ordinary brick (inside) with 15 mm plaster roof construction: suspended plasterboard ceiling, 450 mm air space, 150 mm concrete, 75mm screed, waterproofing no heat transfer across other surfaces window area 3x 1,5 m high in north wall only. ordinary glass with venetian blinds. lights and occupants : from 07: 00 to 18: 00 average light density: 25 w/m2 number of occupants : 5 seated, light office work room temperature 24°c