Question

et2710 engineering statics-fall 2025
exam iii monday 11/24/2025
name: _ w#: _
notes:

• show all your calculations and use neat sketches if needed.
• using or possession of cell phones electronic devices (except calculators) during the exam will be

considered as cheating and may result in further disciplinary actions.

• test duration: 75 minutes.
• for all problems: draw fbd whenever needed,

question 1: (15 points)
choose the right answer for each of the following
(circle one answer):

1. is this truss considered simple truss?

a) yes.
b) no.

1. how many zero - force members in this truss?

a) 3 members b) 4 members
c) 5 members d) 6 members

1. one of the assumptions used when analyzing a simple truss is that the members are

joined together by _.
a) smooth pins b) riveting
c) bolting d) welding

1. frames and machines are different as compared to trusses since they (frames and

machines) have _.
a) only two - force members
b) only multiforce members
c) at least one multiforce member
d) at least one two - force member

1. in a multiforce member, the member is generally subjected to an internal _.

a) normal force
b) shear force
c) bending moment
d) all of the above

Explanation:

1. A simple truss is built by adding triangular units, but this truss has a member (I) not forming basic triangles from a triangular base, so it is not simple.
2. Zero-force members occur where two non-collinear members meet with no load or three members meet (two collinear, one non-collinear with no load). Counting these gives 3.
3. A core assumption for simple truss analysis is members are connected by smooth pins (no moment transfer).
4. Trusses have only two-force members; frames/machines have at least one multi-force member (acted on by ≥3 forces).
5. Multiforce members carry normal force, shear force, and bending moment due to multiple applied forces.

Answer:

1. B) No
2. A) 3 members
3. A) Smooth pins
4. C) At least one multiforce member
5. D) All of the above