Describing Motion
When tracking motion along a single dimension, we use sign conventions to describe direction. For horizontal motion, positive velocity (Vx > 0) means moving right, while negative velocity (Vx < 0) means moving left. Similarly, for vertical motion, positive velocity (Vy > 0) means moving up, while negative velocity (Vy < 0) means moving down.
Position graphs show us where an object is at different times. The slope of a position graph tells us the velocity. Steeper slopes mean faster motion, while flatter slopes indicate slower motion. When a slope increases (gets steeper), the object is speeding up; when it decreases (gets flatter), the object is slowing down.
To interpret position graphs, follow three steps: first, determine position at a specific time by reading the y-axis; second, calculate velocity by finding the slope Δx/Δt; third, determine direction of motion from the sign of the slope positive=right/up,negative=left/down.
💡 Remember: When analyzing motion graphs, the shape matters! A straight line means constant velocity, while curves indicate changing speeds.