Circular bar 1 is attached to the wall by brackets 2 and 3. Bracket 3 is supported by a pin joint at F. Bracket 2 is attached to bracket 3 by bolt assemblies. Bar 1 is subjected to an external load of 5000 N (weight of the bar is negligible). Bracket 2 weighs 400 N and bracket 3 weighs 300 N. Bar 1 is made of a material which can withstand a maximum normal stress (sigma) =10 MPa and the bolted connections are made of material which can withstand a maximum shear stress ….

Abrake has a normal braking torque of 2.8 kip in and heat-dissipating cast-iron surfaces whose mass is 40 lbm. suppose a load is brought to rest in 8.0 s from an initial angular speed of 1600 rev/min using the normal braking torque; estimate the temperature rise of the heat dissipating surfaces.

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?

Tech a says never use a water hose to clean up dust after a repair. tech b says never use a floor scrubber to clean up dust after repairs. who is correct?