Consider pressurized liquid water flowing at m = 0.1 kg/s in a circular tube of diameter D = 0.1 m and length L = 6 m.
(a) If the water enters at Tm, i = 500 K and the surface temperature of the tube is Ts = 510 K, determine the water outlet temperature Tm, o.
(b) If the water enters at Tm, i = 300 K and the surface temperature of the tube is Ts = 310 K, determine the water outlet temperature Tm, o.

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