1. Three identical circular disks A, B, and C are welded
to the ends of three identical solid circular bars
(see figure). The bars lie in a common plane and the
disks lie in planes perpendicular to the axes of the
bars. The bars are welded at their intersection D to
form a rigid connection. Each bar has diameter
d1 = 0.5 in. and each disk has diameter d2 = 3.0 in.
Forces P1, P2, and P3 act on disks A, B, and C,
respectively, thus subjecting the bars to torsion.
If P1 = 28 lb, what is the maximum shear stress
tmax in any of the three bars?
R//tmax=4840 psi
2.
3. A circular bar AB with ends fixed against rotation
has a hole extending for half of its length
(see figure). The outer diameter of the bar is
d2 = 3.0 in. and the diameter of the hole is
d1 = 2.4 in. The total length of the bar is L = 50 in.
At what distance x from the left-hand end of
the bar should a torque T0 be applied so that
the reactive torques at the supports will be equal?
R// x=30.12in
4.
5.
6. Three solid shafts, each of 3/4-in. diameter,
are connected by the gears as shown.
Knowing that G = 11.2 E6 psi, determine
(a) the angle through which end A of shaft
AB rotates,
(b) the angle through which end E
of shaft EF rotates.
R// α_A=24.5° α_E=19.37°
