Aspecimen of a 4340 steel alloy with a plane strain fracture toughness of 54.8 mpa (50 ksi ) is exposed to a stress of 1225 mpa (177700 psi). assume that the parameter y has a value of 0.98. (a) if the largest surface crack is 0.8 mm (0.03150 in.) long, determine the critical stress .

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

Asingle-geared blanking press has a stroke of 200 mm and a rated capacity of 320 kn. a cam driven ram is assumed to be capable of delivering the full press load at constant force during the last 15 percent of a constant-velocity stroke. the camshaft has an average speed of 90 rev/min and is geared to the flywheel shaft at a 6: 1 ratio. the total work done is to include an allowance of 16 percent for friction a) estimate the maximum energy fluctuation b) find the rim weight for an effective diameter of 1.2 m and a coefficient of speed fluctuation of 0.10

The filament of an incandescent lamp has a temperature of 2000k. calculate the fraction of radiation emitted in the visible light band if the filament is approximated as blackbody