A rectangular RCC machine foundation of size 3.0 x 3.0 x 0.8m thick is supporting a machine of weight is 10kN. The machine transmits an unbalanced vertical load passing through the combined CG of the machine and foundation whose amplitude is 8[1-sin/4t]kN Soil medium has the following properties: Young’s modulus, E=1.2 x105 kN/m2. Poisson’s ratio, v=0.3. Unit weight of soil and concrete, s=17 kN/m3. c=17 kN/m3 Find the response of the system and natural frequency using Elastic half-space approach for vertical and sliding vibration

The mass flow rate of the fluid remains constant in all steady flow process. a)- true b)- false

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.

What is creep? what is stress relaxation?