I meant in physics

In physics, vectors represent quantities that have both magnitude and direction. This is crucial for understanding motion, forces, and fields.

• Examples: Velocity (speed and direction), acceleration (rate of change of velocity), force (strength and direction of a push or pull), displacement (change in position).
• Scalars are quantities with only magnitude: mass, speed, temperature, time.

Vectors are often represented by arrows. The length of the arrow shows the magnitude, and the arrowhead shows the direction.

• In equations, vectors are often written in bold (e.g., v for velocity) or with an arrow above (e.g., $\vec{v}$).
• We can also use component form. In 2D, a vector A can be written as (Aₓ, Aᵧ), meaning it has a component Aₓ along the x-axis and Aᵧ along the y-axis.
• In 3D, it's (Aₓ, Aᵧ, A<0xE2><0x82><0x9B>).
• We can also use unit vectors: A = Aₓi + Aᵧj + A<0xE2><0x82><0x9B>k, where i, j, and k are unit vectors in the x, y, and z directions, respectively (magnitude 1).

The magnitude of a vector is its size or length. For a vector A = (Aₓ, Aᵧ), the magnitude |A| is found using the Pythagorean theorem: |A| = √(Aₓ² + Aᵧ²) For a 3D vector A = (Aₓ, Aᵧ, A<0xE2><0x82><0x9B>): |A| = √(Aₓ² + Aᵧ² + A<0xE2><0x82><0x9B>²)

Example: If a force F = (3 N, 4 N), its magnitude is |F| = √(3² + 4²) = √(9 + 16) = √25 = 5 N.

To add vectors in physics, we add their corresponding components. This is essential for finding the net force or resultant displacement.
If A = (Aₓ, Aᵧ) and B = (Bₓ, Bᵧ), then:
A + B = (Aₓ + Bₓ, Aᵧ + Bᵧ)

Example: If you push a box with force F₁ = (10 N, 0 N) (horizontally) and another person pushes with F₂ = (0 N, 5 N) (vertically), the net force F_net is:
F_net = F₁ + F₂ = (10 N + 0 N, 0 N + 5 N) = (10 N, 5 N).
The magnitude of the net force is |F_net| = √(10² + 5²) = √(100 + 25) = √125 ≈ 11.2 N.

Vector subtraction is used, for example, to find the change in velocity (which is acceleration).
If A = (Aₓ, Aᵧ) and B = (Bₓ, Bᵧ), then:
A - B = (Aₓ - Bₓ, Aᵧ - Bᵧ)

Example: If the initial velocity v₁ = (10 m/s, 0 m/s) and the final velocity v₂ = (0 m/s, 10 m/s), the change in velocity Δv is:
Δv = v₂ - v₁ = (0 m/s - 10 m/s, 10 m/s - 0 m/s) = (-10 m/s, 10 m/s).

Ready for the next step? We can cover scalar multiplication, dot product, or cross product.