In order to test the thermal insulation of a given material, you build a hollow cube of 25.0 cm of its ring using 1.5 cm thick laminas. You put a thermometer and a 100 W heater inside the box. Once the balance ˆ has been reached temperature inside the box and 90 °C and while the outside temperature is 25 °C °C. Determine the resistance of the box.

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

Steel is coated with a thin layer of ceramic to protect against corrosion. what do you expect to happen to the coating when the temperature of the steel is increased significantly? explain.

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.