Determine the principal planes and the principal stresses for the state of plane stress resulting from the superposition of the two states of stress shown. given: x 50 mpa and y 30 mpa. ay 80 mpa 30° + the orientation of the principal plane in the first quadrant is 120 the orientation of the principal plane in the second quadrant is 210 mpa, and the minimum principal the maximum principal stress is mра. stress is

Asolid cylinder is concentric with a straight pipe. the cylinder is 0.5 m long and has an outside diameter of 8 cm. the pipe has an inside diameter of 8.5 cm. the annulus between the cylinder ad the pipe contains stationary oil. the oil has a specific gravity of 0.92 and a kinematic viscosity of 5.57 x 10-4 m2/s. most nearly, what is the force needed to move the cylinder along the pipe at a constant velocity of 1 m/s?