1. Easy
A B C D E F G H 35 kN 10 kN 40 kN 40 kN 25 kN 4 × 4 m 3 m Exactly one member of this truss carries no force under these loads. Which is the zero-force member? Click it in the diagram.
C: 35 kN ↓ D: 10 kN ↓ F: 40 kN ↓ G: 40 kN ↓ H: 25 kN ↓
1 member AB 2 member BC 3 member CD 4 member DE 5 member FG 6 member GH 7 member AF 8 member HE 9 member BF 10 member CG 11 member DH 12 member FC 13 member HC 2. Easy
AB BC AC A C B 40 kN 5 m 2.5 m 3 m Use the method of joints to find the force FAB in member AB. Give tension as positive and compression as negative.
span = 5 m height = 3 m B is 2.5 m from A vertical load = 40 kN
FAB = kN
3. Medium
Use the method of joints to find the force FAC in member AC. Give tension as positive and compression as negative.
span = 6 m height = 2 m B is 4 m from A vertical load = 25 kN
FAC = kN
4. Medium
Use the method of joints to find the force FBC in member BC. Give tension as positive and compression as negative.
span = 8 m height = 2 m B is 3 m from A vertical load = 40 kN
FBC = kN
5. Hard
AB BC AC A C B 55 kN 30 kN 4 m 3 m 2 m Use the method of joints to find the force FAC in member AC. Give tension as positive and compression as negative.
span = 4 m height = 2 m B is 3 m from A vertical load = 55 kN horizontal load = 30 kN ←
FAC = kN
6. Hard
A B C D E F G H 15 kN 30 kN 35 kN 30 kN 4 × 4 m 3 m Exactly one member of this truss carries no force under these loads. Which is the zero-force member? Click it in the diagram.
D: 15 kN ↓ F: 30 kN ↓ F: 35 kN → H: 30 kN ↓
1 member AB 2 member BC 3 member CD 4 member DE 5 member FG 6 member GH 7 member AF 8 member HE 9 member BF 10 member CG 11 member DH 12 member BG 13 member DG
Answer key 1. member BF2. FAB = −26.03 kN3. FAC = 16.67 kN4. FBC = −40.39 kN5. FAC = 13.13 kN6. member CGFull step-by-step solutions: practise this topic on examproblems.com.