An offshore drilling rig is being towed out to sea. what is the maximum distance away that the navigation lights can still be seen by an observer standing on the shoreline? the observer's eye height is 5'6", and the uppermost navigation light is 168 ft above the water.

At steady state, air at 200 kpa, 325 k, and mass flow rate of 0.5 kg/s enters an insulated duct having differing inlet and exit cross-sectional areas. the inlet cross-sectional area is 6 cm2. at the duct exit, the pressure of the air is 100 kpa and the velocity is 250 m/s. neglecting potential energy effects and modeling air as an 1.008 kj/kg k, determine ideal gas with constant cp = (a) the velocity of the air at the inlet, in m/s. (b) the temperature of the air at the exit, in k. (c) the exit cross-sectional area, in cm2

Asolid steel sphere (k=63.9 w m-1 k-1 , ? =7832 kg m-3 , c=0.523 kj kg-1 k-1 ), 100 mm in diameter is initially at a uniform temperature of 500o c and is suddenly quenched in a large oil bath for which t? = 100o c and h = 3200 w m-2 k-1. estimate the time required for the sphere to cool to 200o c and to 110o c

What is the maximum height from which a mass of 30 kg can fall on to a flange on the lower end of a vertical rod of length 1.0 m and diameter 20 mm, the upper end being rigidly fixed, if the stress in the rod is not to exceed 80 mpa? the tensile modulus of the rod is 200 gpa.