Consider a thin suspended hotplate that measures 0.2 m × 0.2 m. the isothermal plate has a mass of 3.75 kg, a specific heat of 2770 j/kg·k, and a temperature of 275°c. the ambient air temperature is 25°c and the surroundings temperature is 25°c. if the convection coefficient is 6.4 w/m2·k and the emissivity of the plate is ɛ= 0.42, determine the time rate of change of the plate temperature, d⁢t/d⁢t , when the plate temperature is 275°c. evaluate the magnitude of the heat losses by convection and by radiation.

What precautions should you take to prevent injuries when dealing with heavy loads?

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

The drive force for diffusion is 7 fick's first law can be used to solve the non-steady state diffusion. a)-true b)-false