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PROBLEM (9.50) For the bracket of b by h rectangular cross section, loaded as shown in Fig. P9.50,
determine:
(a) The maximum normal stress.
(b) The location of the neutral axis.
Given: P = 8 kips,
b = 1in., h = 4 in.
SOLUTION
1(4)3
= 5.33 in.4
12
P = 8 kips
M = 8 × 10 3 ( 2) = 16 kip ⋅ in.
(a) At the top fibers:
P Mc 8 × 103 16 × 103 (2)
σt = −
=
−
A I
4
5.33
= 2 − 6 = −4 ksi
A = bh = 1(4) = 4 in.2
I=
At the bottom fibers:
σ b = 2 + 6 = 8 ksi
(b) Equation (9.13):
0 = 2 × 103 −
y n = 0.667 in.
16 ×103 yn
5.33
σt
N.A
yn
x
σb
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