Q. A beam is subjected to a moment of 50 kNm. If the section modulus is 10 cm^3, what is the bending stress in the beam?
A.
5 MPa
B.
10 MPa
C.
15 MPa
D.
20 MPa
Solution
Bending stress (σ) is calculated using the formula σ = M/Z, where M is the moment and Z is the section modulus. Here, σ = 50 kNm / 10 cm^3 = 50,000 Nm / 0.00001 m^3 = 5 MPa.
Q. A simply supported beam has a length of 8 m and is subjected to a uniformly distributed load of 4 kN/m. What is the deflection at the center of the beam?
A.
0.025 m
B.
0.05 m
C.
0.1 m
D.
0.075 m
Solution
The deflection at the center of a simply supported beam under a uniform load is given by δ = 5wL^4 / (384EI). Substituting w = 4 kN/m, L = 8 m, E = 200 GPa, and I = 0.0001 m^4 gives δ = 0.05 m.
Q. A strip footing is placed on a sandy soil with a friction angle of 30 degrees. What is the approximate value of the bearing capacity factor N_q?
A.
1.5
B.
2.5
C.
3.5
D.
4.5
Solution
For a friction angle of 30 degrees, the bearing capacity factor N_q can be approximated using the formula N_q = e^(π * tan(φ)) * tan(45 + φ/2). For φ = 30 degrees, N_q is approximately 3.5.
Q. For a cantilever beam with a point load at the free end, what is the deflection at the free end?
A.
WL^3/(3EI)
B.
WL^3/(12EI)
C.
WL^2/(2EI)
D.
WL^4/(8EI)
Solution
The deflection (δ) at the free end of a cantilever beam with a point load (W) at the end is given by δ = WL^3/(3EI), where E is the modulus of elasticity and I is the moment of inertia.
Q. For a cantilever beam with a uniform distributed load, what is the formula for the maximum shear force at the fixed support?
A.
w * L
B.
0
C.
w * L / 2
D.
w * L^2 / 2
Solution
The maximum shear force (V) at the fixed support of a cantilever beam with a uniform distributed load (w) is V = w * L, where L is the length of the beam.
Q. For a cantilever beam with a uniform distributed load, what is the formula for the maximum deflection at the free end?
A.
5wL^4 / 384EI
B.
wL^4 / 8EI
C.
wL^3 / 3EI
D.
wL^3 / 48EI
Solution
The maximum deflection (δ) at the free end of a cantilever beam with a uniform distributed load (w) is given by δ = 5wL^4 / 384EI, where E is the modulus of elasticity and I is the moment of inertia.
Q. For a foundation subjected to a vertical load, what is the primary mode of failure?
A.
Shear failure
B.
Bearing capacity failure
C.
Settlement failure
D.
Tensile failure
Solution
The primary mode of failure for a foundation subjected to vertical loads is typically bearing capacity failure, which occurs when the soil can no longer support the applied load.
Q. For a frame structure, which method is used to analyze the internal forces and moments?
A.
Method of Joints
B.
Method of Sections
C.
Stiffness Method
D.
Virtual Work Method
Solution
The Stiffness Method is commonly used to analyze frame structures by considering the stiffness of each member and the overall deformation of the structure.