To a good approximation, the dynamic viscosity , the thermal conductivity , and the specific heat are independent of pressure. In what manner do the kinematic viscosity and thermal diffusivity vary with pressure for an ideal gas? Determine of air at 350 K for various pressures. Assuming a transition Reynolds number of 1 × 105, determine the distance from the leading edge of a flat plate at which transition will occur for air at 350 K at various pressures with [infinity] 2 m/s.

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

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg. m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?

Precipitation hardening can be achieved in many light alloys by a three-step heat treatment. what is carried out and what is the purpose at each step? why is such a treatment necessary based on the nucleation and growth theory of phase transformation. compare this treatment with tempering martensite for carbon steels (similarities and differences).