A cylindrical transmission shaft of length 1.5 m and diameter 100 mm is made of a linear elastic material with a shear modulus of 80 GPa. While operating at 500 rpm, the angle of twist across its length is found to be 0.5 degrees.
The power transmitted by the shaft at this speed is _______kW. (Rounded off to two decimal places)
Take π = 3.14.
A shaft of length L is made of two materials, one in the inner core and the other in the outer rim, and the two are perfectly joined together (no slip at the interface) along the entire length of the shaft. The diameter of the inner core is d; and the external diameter of the rim is d0, as shown in the figure. The modulus of rigidity of the core and rim materials are Gi and G0, respectively. It is given that d0 = 2di and Gi = 3G0. When the shaft is twisted by application of a torque along the shaft axis, the maximum shear stress developed in the outer rim and the inner core turn out to be τ0 and τi, respectively. All the deformations are in the elastic range and stress-strain relations are linear. Then the ratio τi/τ0 is (round off to 2 decimal places).
The vertical deflection at point $$A$$ is