An ordinary egg can be approximated as a 5.5-cmdiameter sphere whose properties are roughly k 5 0.6 W/m·K and a 5 0.14 3 1026 m2/s. The egg is initially at a uniform temperature of 8°C and is dropped into boiling water at 97°C. Taking the convection heat transfer coefficient to be h 5 1400 W/m2·K, determine how long it will take for the center of the egg to reach 70°C. Solve this problem using analytical one-term approximation method (not the Heisler charts).

On a average work day more than work place firs are reorted

Ahelical coil spring has a mean diameter of 50 mm, a wire diameter of 5.5 mm and is wound with a pitch of 10 mm. the spring steel has an ultimate strength of 1250 mpa. find the force needed to compress the spring solid and the wire stress in this condition. state whether the spring will return to its initial length.

An air-conditioning system consists of a heating section and an evaporative cooler. air enters the heating section at 10°c and 70 percent relative humidity at a rate of 30m^3/min, and it leaves the evaporative cooler at 20°c and 60 percent relatively humidity. if the air conditioning system operates at a total pressure of 98 kpa, determine (a) the temperature and relative humidity of the air when it leaves the heating section, (b) the rate of heat transfer in the heating section, and (c) the rate of water added to air in the evaporative cooler