Question

The quadriceps muscles pull on the patella simultaneously. Below are the forces from each

Answer 1

Based on the calculation of the resultant of vector forces:

1. the resultant force due to the quadriceps is 1795 N
2. the resultant force due to the quadriceps is 1975 N. Training and strengthening the vastus medialis results in a greater force of muscle contraction.

What is the resultant force due to the quadriceps?

The resultant of more than two vector forces is given by:

• F = √Fₓ² + Fₙ²

where:

• Fₓ is the sum of the horizontal components of the forces
• Fₙ is the sum of the vertical components of the forces
• Fx = F₁cosθ + F₂cosθ + F₃cosθ + F₄cosθ
• Fₙ = F₁sinθ + F₂sinθ + F₃sinθ + F₄sinθ
• F₁ = 680N, θ = 90 = 30 = 120°
• F₂ = 220 N, θ = 90 + 16 = 106°
• F₃ = 600 N, θ = 90 + 15 = 105°
• F₄ = 480 N, θ = 90 - 35 = 55°

then:

Fx = 680 * cos 120 + 220 * cos 106 + 600 * cos 105 + 480 * cos 55

Fx = -280.6 N

Fₙ = 680 * sin 120 + 220 * sin 106 + 600 * sin 105 + 480 * sin 55

Fₙ = 1773.1 N

then:

F = √(-280.6)² + ( 1773.1)²

F = 1795.16 N

F ≈ 1795 N

Therefore, the resultant force due to the quadriceps is 1795 N

What would happen if the vastus medialis was trained and strengthened to contract with 720N of force?

From the new information provided:

• F₁ = 680N, θ = 90 = 30 = 120°
• F₂ = 220 N, θ = 90 + 16 = 106°
• F₃ = 600 N, θ = 90 + 15 = 105°
• F₄ = 720 N, θ = 90 - 35 = 55°

then:

Fx = 680 * cos 120 + 220 * cos 106 + 600 * cos 105 + 720 * cos 55

Fx = -142.95 N

Fₙ = 680 * sin 120 + 220 * sin 106 + 600 * sin 105 + 720 * sin 55

Fₙ = 1969.72 N

then:

F = √(-142.95)² + ( 1969.72)²

F = 1974.9 N

F ≈ 1975 N

Therefore, the resultant force due to the quadriceps is 1975 N.

Training and strengthening the vastus medialis results in a greater force of muscle contraction.

Learn more about resultant of forces at: brainly.com/question/25239010