There are no correct descriptive statement on the list you included.
Answer:
a) τmax = 586.78 P.S.I.
b) σmax = 15942.23 P.S.I
Explanation:
D = 3.81 in
d = 3.24 in
P = 930 lb
L = 3.7 ft = 44.4 in
a) The maximum horizontal shear stress can be obtained as follows
τ = V*Q / (t*I)
where
V = P = 930 lb
Q = (2/3)*(R³- r³) = (1/12)*(D³- d³) = (1/12)*((3.81 in)³- (3.24 in)³)
⇒ Q = 1.7745 in³
t = D - d = 3.81 in - 3.24 in = 0.57 in
I = (π/64)*(D⁴-d⁴) = (π/64)*((3.81 in)⁴- (3.24 in)⁴) = 4.9341 in⁴
then
τ = (930 lb)*(1.7745 in³) / (0.57 in*4.9341 in⁴)
⇒ τmax = 586.78 P.S.I.
b) We can apply the following equation in order to get the maximum tension bending stress in the pipe
σmax = Mmax *y / I
where
Mmax = P*L = 930 lb*44.4 in = 41292 lb-in
y = D/2 = 3.81 in /2 = 1.905 in
I = 4.9341 in⁴
then
σmax = (41292 lb-in)*(1.905 in) / (4.9341 in⁴) = 15942.23 P.S.I
