Learning Goal
Part of: Motion in Two Dimensions — 2 of 5 chapter items
Vector Addition and Subtraction: Analytical Methods
"For a two-dimensional vector, a **component** is a piece of a vector that points in either the x- or y-direction. Every 2-d vector can be expressed as a sum of its x and y components."
"To find the magnitude *A* and direction θ of a vector from its perpendicular components **A**_x and **A**_y, we use the following relationships: A = √(A_x² + A_y²), θ = tan⁻¹(A_y/A_x)."
"Note that tan⁻¹(θ) gives an angle in the first quadrant if A_y/A_x > 0 and in the fourth quadrant if A_y/A_x < 0. If, in fact, both A_x and A_y are negative, or if A_x is negative and A_y positive, then θ, measured from the positive x direction, is tan⁻¹(θ) + 180°."
Show moreShow less
"For a two-dimensional vector, a component is a piece of a vector that points in either the x- or y-direction. Every 2-d vector can be expressed as a sum of its x and y components."
"To find the magnitude A and direction θ of a vector from its perpendicular components A_x and A_y, we use the following relationships: A = √(A_x² + A_y²), θ = tan⁻¹(A_y/A_x)."
"Note that tan⁻¹(θ) gives an angle in the first quadrant if A_y/A_x > 0 and in the fourth quadrant if A_y/A_x < 0. If, in fact, both A_x and A_y are negative, or if A_x is negative and A_y positive, then θ, measured from the positive x direction, is tan⁻¹(θ) + 180°."
What you'll learn
- Define the x- and y-components of a two-dimensional vector
- Resolve a vector into components using A_x = A cos θ and A_y = A sin θ
- Reconstruct a vector's magnitude and direction from its components using A = √(A_x² + A_y²) and θ = tan⁻¹(A_y/A_x)
- Add and subtract vectors analytically using the four-step component procedure
- Apply the quadrant rule to interpret the inverse-tangent result correctly
Prerequisites
Slides
Interactive presentations perfect for visual learners • In development
Slides
In development
Not yet available • Check back soon!