Let’s solve this step by step.
---
Part I: Find the x and y components of each vector
We use trigonometry:
- x-component = magnitude × cos(angle)
- y-component = magnitude × sin(angle)
Angle is measured from the positive x-axis (standard position).
---
First vector: 12 m at 30°
x = 12 × cos(30°) = 12 × (√3/2) ≈ 12 × 0.866 =
10.39 m
y = 12 × sin(30°) = 12 × 0.5 =
6.00 m
---
Second vector: 25 m/s at 60°
x = 25 × cos(60°) = 25 × 0.5 =
12.5 m/s
y = 25 × sin(60°) = 25 × (√3/2) ≈ 25 × 0.866 =
21.65 m/s
---
Third vector: 15 m/s at 150°
Note: 150° is in second quadrant → x negative, y positive.
x = 15 × cos(150°) = 15 × (-√3/2) ≈ 15 × (-0.866) =
-12.99 m/s
y = 15 × sin(150°) = 15 × 0.5 =
7.50 m/s
---
Add the following vectors
---
First addition: 12 m/s at 20° + 12 m/s at 70°
Break into components:
Vector 1 (20°):
x₁ = 12 × cos(20°) ≈ 12 × 0.9397 =
11.28 m/s
y₁ = 12 × sin(20°) ≈ 12 × 0.3420 =
4.10 m/s
Vector 2 (70°):
x₂ = 12 × cos(70°) ≈ 12 × 0.3420 =
4.10 m/s
y₂ = 12 × sin(70°) ≈ 12 × 0.9397 =
11.28 m/s
Total:
x_tot = 11.28 + 4.10 =
15.38 m/s
y_tot = 4.10 + 11.28 =
15.38 m/s
---
Second addition: 50 m at 135° + 30 m at 90°
Vector 1 (135°):
This is in second quadrant.
x₁ = 50 × cos(135°) = 50 × (-√2/2) ≈ 50 × (-0.7071) =
-35.36 m
y₁ = 50 × sin(135°) = 50 × (√2/2) ≈ 50 × 0.7071 =
35.36 m
Vector 2 (90°): straight up
x₂ = 30 × cos(90°) = 30 × 0 =
0 m
y₂ = 30 × sin(90°) = 30 × 1 =
30 m
Total:
x_tot = -35.36 + 0 =
-35.36 m
y_tot = 35.36 + 30 =
65.36 m
---
Final Answer:
Part I:
First vector: x = 10.39 m, y = 6.00 m
Second vector: x = 12.5 m/s, y = 21.65 m/s
Third vector: x = -12.99 m/s, y = 7.50 m/s
Addition 1: x₁ = 11.28 m/s, y₁ = 4.10 m/s; x₂ = 4.10 m/s, y₂ = 11.28 m/s; x_tot = 15.38 m/s, y_tot = 15.38 m/s
Addition 2: x₁ = -35.36 m, y₁ = 35.36 m; x₂ = 0 m, y₂ = 30 m; x_tot = -35.36 m, y_tot = 65.36 m
Parent Tip: Review the logic above to help your child master the concept of vector worksheet.