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PROBLEM (9.30) Determine the maximum principal stress and the maximum shearing stress for a d
= 50-mm-diameter shaft in equilibrium shown in Fig. P9.30.
Assumption: The bearings at A and B are taken to be frictionless; they act as simple support.
SOLUTION
4 kN
A
0.4 m
0.6 m
RA = 2.4 kN
∑T = 0 :
B
RB = 1.6 kN
T = 2 × 10 3 (0.2) = 400 N ⋅ m
M c = M max = 2.4 × 10 3 (0.4) = 960
σx =
C
τ=
Equation (9.1):
32 M
16 M 2
16T
16
) + (− 3 ) 2 =
(M ± M 2 + T 2 )
σ 1,2 =
± (
3
3
2π d
πd
πd
πd3
16
=
(960 ± 9602 + 4002 ) = (39.114 ± 42.373)10 6
π (0.05)3
Thus,
σ 1 = 81.5 MPa
σ 2 = −3.26 MPa
τ max = 42.4 MPa
32M
πd3
16T
πd3
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