Resolution of a Force
Statics · FE Reference Handbook section
Core formulas for this FE topic
Definitions, applicability, units, assumptions and worked examples for each relation.
Worked exam-style examples
The four ways this section is written on the real exam — thoughts first, then equations, then substitution.
Two forces act at a gusset plate: 20 kN at 43° and 65 kN at 130° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = -27.15 kN, ΣF_y = 63.43 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 85 kN (magnitudes added)
- 27.15 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 36 kN at 20° and 90 kN at 139° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = -34.09 kN, ΣF_y = 71.36 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 126 kN (magnitudes added)
- 34.09 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 80 kN at 37° and 58 kN at 126° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = 29.80 kN, ΣF_y = 95.07 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 138 kN (magnitudes added)
- 29.80 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 31 kN at 34° and 68 kN at 120° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = -8.30 kN, ΣF_y = 76.22 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 99 kN (magnitudes added)
- 8.30 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 64 kN at 45° and 48 kN at 147° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = 5.00 kN, ΣF_y = 71.40 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 112 kN (magnitudes added)
- 5.00 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 87 kN at 57° and 74 kN at 143° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = -11.72 kN, ΣF_y = 117.5 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 161 kN (magnitudes added)
- 11.72 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 68 kN at 62° and 33 kN at 141° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = 6.28 kN, ΣF_y = 80.81 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 101 kN (magnitudes added)
- 6.28 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 58 kN at 48° and 80 kN at 127° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = -9.34 kN, ΣF_y = 107.0 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 138 kN (magnitudes added)
- 9.34 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 68 kN at 22° and 33 kN at 165° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = 31.17 kN, ΣF_y = 34.01 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 101 kN (magnitudes added)
- 31.17 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force
Two forces act at a gusset plate: 83 kN at 50° and 89 kN at 154° from the positive x-axis. Resolve each force into components and determine the magnitude and direction of the resultant force.
Given
Find
Resultant force magnitude R and its direction
Start with the thinking
- A force system is resolved by summing x- and y-components separately.
- The resultant of concurrent forces is the vector sum, never the arithmetic sum of magnitudes.
Step-by-step solution
Formula
F₁ components
F₂ components
Sums — ΣFₓ = -26.64 kN, ΣF_y = 102.6 kN
Formula — R = √(ΣFₓ² + ΣF_y²)
Substituting
Why the other options are there
- 172 kN (magnitudes added)
- 26.64 kN (y-component dropped)
Reference: FE Reference Handbook — Statics → Resolution of a Force