Afriction clutch is used to rotate a machine from a shaft rotating at a uniform speed of 250 r. p.m. the disc-type clutch has both of its sides effective with a friction coefficient of 0.3. the outer and the inner diameters of the friction plate are 200 mm and 120 mm respectively. the intensity of pressure is not to be more than 100 kn/m², calculate i. the power transmitted by this clutch based on the theory of uniform wear, ii. the intensity of pressure if the condition of uniform pressure is considered, and iii. the ratio of power transmitted with uniform wear to that with uniform pressure.

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