1. What is the unit of bending moment in SI units?
A. Newton
B. Newton-meter
C. Newton-second
D. Joule
Answer: b) Newton-meter
Rationale: The unit of bending moment is the Newton-meter (Nm), which is the
product of force (in Newtons) and the distance from the support (in meters).
2. What is the primary function of a beam in a structure?
A. To carry vertical loads
B. To resist bending moments
C. To resist shear forces
D. All of the above
Answer: d) All of the above
Rationale: Beams in structures are designed to resist vertical loads, shear forces, and
bending moments to ensure stability and strength.
,3. A beam is considered to be in elastic bending when:
A. It is subjected to high deflection
B. The material is in the plastic range of deformation
C. The material’s deformation is within the elastic range
D. It is subjected to shear stress only
Answer: c) The material’s deformation is within the elastic range
Rationale: Elastic bending occurs when the beam’s material deforms within the elastic
limit, meaning it will return to its original shape once the load is removed.
4. For a cantilever beam with a uniform load, the maximum deflection occurs at:
A. The support
B. At midspan
C. At the free end
D. At quarter span
Answer: c) At the free end
Rationale: For a cantilever beam with a uniform load, the maximum deflection occurs
at the free end, where the displacement due to bending is the greatest.
, 5. What is the formula for the maximum bending stress in a beam subjected to a
bending moment MMM?
A. σ=MI×x\sigma = \frac{M}{I} \times xσ=IM×x
B. σ=MI×y\sigma = \frac{M}{I} \times yσ=IM×y
C. σ=MI×L\sigma = \frac{M}{I} \times Lσ=IM×L
D. σ=My\sigma = \frac{M}{y}σ=yM
Answer: b) σ=MI×y\sigma = \frac{M}{I} \times yσ=IM×y
Rationale: The maximum bending stress in a beam is given by σ=MI×y\sigma =
\frac{M}{I} \times yσ=IM×y, where MMM is the bending moment, III is the moment
of inertia, and yyy is the distance from the neutral axis.
6. The bending moment at the midpoint of a simply supported beam with a uniform
load is:
A. Zero
B. Equal to the reaction force
C. Maximum
D. Equal to half the applied load
Answer: c) Maximum
A. Newton
B. Newton-meter
C. Newton-second
D. Joule
Answer: b) Newton-meter
Rationale: The unit of bending moment is the Newton-meter (Nm), which is the
product of force (in Newtons) and the distance from the support (in meters).
2. What is the primary function of a beam in a structure?
A. To carry vertical loads
B. To resist bending moments
C. To resist shear forces
D. All of the above
Answer: d) All of the above
Rationale: Beams in structures are designed to resist vertical loads, shear forces, and
bending moments to ensure stability and strength.
,3. A beam is considered to be in elastic bending when:
A. It is subjected to high deflection
B. The material is in the plastic range of deformation
C. The material’s deformation is within the elastic range
D. It is subjected to shear stress only
Answer: c) The material’s deformation is within the elastic range
Rationale: Elastic bending occurs when the beam’s material deforms within the elastic
limit, meaning it will return to its original shape once the load is removed.
4. For a cantilever beam with a uniform load, the maximum deflection occurs at:
A. The support
B. At midspan
C. At the free end
D. At quarter span
Answer: c) At the free end
Rationale: For a cantilever beam with a uniform load, the maximum deflection occurs
at the free end, where the displacement due to bending is the greatest.
, 5. What is the formula for the maximum bending stress in a beam subjected to a
bending moment MMM?
A. σ=MI×x\sigma = \frac{M}{I} \times xσ=IM×x
B. σ=MI×y\sigma = \frac{M}{I} \times yσ=IM×y
C. σ=MI×L\sigma = \frac{M}{I} \times Lσ=IM×L
D. σ=My\sigma = \frac{M}{y}σ=yM
Answer: b) σ=MI×y\sigma = \frac{M}{I} \times yσ=IM×y
Rationale: The maximum bending stress in a beam is given by σ=MI×y\sigma =
\frac{M}{I} \times yσ=IM×y, where MMM is the bending moment, III is the moment
of inertia, and yyy is the distance from the neutral axis.
6. The bending moment at the midpoint of a simply supported beam with a uniform
load is:
A. Zero
B. Equal to the reaction force
C. Maximum
D. Equal to half the applied load
Answer: c) Maximum
