Ahollow steel shaft with a diameter ratio of 0.75 and a length of 4 m is required to transmit 1 mw at 120 rev/min. the maximum shear stress is not to exceed 70 mn/m2 nor is the overall angle of twist to exceed 1.75o. determine the following. (i)the necessary outside diameter of the shaft so that both of the above limitations are satisfied. (ii)the actual maximum shear stress and the actual angle of twist. assume the modulus of rigidity for steel is 80 gpa

An air conditioning system consist of a 5 cm diameter pipe, operating at a pressure of 200 kpa. the air initially enters the pipe at 15°c with a velocity of 20 m/s and relative humidity of 80%. if the heat supply throughout the process is 960 w, determine the relative humidity and the temperature at the outlet

Ahot wire operates at a temperature of 200°c while the air temperature is 20°c. the hot wire element is a tungsten wire of 5 um diameter and 2 mm in length. plot using excel current, heat transfer and heat generated by the wire for air velocity varying from 1-10 m/s in steps of lm/s? matlab the sensor voltage output, resistance, or assume nu 0.989 re033pr13 take air properties at tr (200°c20°c)/2 = 110°c properties of tungsten: c 0.13 kj/kg.k 3 p 19250 kg/m k (thermal conductivity) = 174 w/m.k

Modern high speed trains do not have perpendicular expansion gaps where rails are joined end-to-end any more they are mostly welded together but what might happen if there was a spell of particularly hot weather that causes inspection of the tracks?