TwiddleLab / Math / Vectors and Matrices

Arrows That Move Things

Lesson 1 of 12 · 5 min · Free, no account needed

What you will learn

• A vector is a move: how far across and how far up.
• We write it with two components, like (3, 2). Minus means left or down.
• The same arrow works from any start: a vector is a shift, not a place.

Start the lesson

How the lesson goes

1. In a game, this critter moves 3 right and 2 up every frame.

   Where is it after one frame? Tap that spot.

   A move only needs two numbers: how far across and how far up. Here 3 and 2.

2. Feed the critter. Drag the arrow head onto each berry.

   Watch the card: it writes your arrow as two numbers.

3. Three critters, one arrow. Send them all home.

   Drag the solid arrow head. Every critter copies the same move.

4. That arrow is called a vector.

   A vector is a move: an arrow from its tail to its head.

   Its components say how far across and how far up: (3, 2). Minus means left or down.

   The same arrow can start anywhere. A vector is a shift, not a place.

5. Design your critter's hop.

   It has to jump over the river. Pick x and y with the chips.

   Only the up part decides if it clears the river, so any vector with y at least 3 works.

6. Game: courier. Deliver four orders.

   Each order is a vector. Drag the arrow to match it, then Send. Fewest misses wins.

7. A vector is a move. Your hop works from anywhere.

   Drop critters all over the map. They all use your hop.

Next lesson: How Long Is an Arrow? · Part of the course: Vectors and Matrices

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