Table of Contents
What Is Velocity?
Velocity is a vector quantity that describes the rate of change of position with respect to time. Unlike speed (scalar), velocity includes both magnitude and direction. An object moving north at 10 m/s has a different velocity than one moving east at 10 m/s.
Velocity is one of the most fundamental concepts in kinematics. It connects position to time through differentiation and connects to acceleration through the first derivative of velocity.
Kinematic Equations
Speed Comparisons
| Object | m/s | km/h |
|---|---|---|
| Walking | 1.4 | 5 |
| Sprint | 10 | 36 |
| Highway Car | 31 | 112 |
| Sound in Air | 343 | 1,235 |
| Earth Orbit | 29,800 | 107,280 |
Frequently Asked Questions
Speed vs velocity?
Speed is the magnitude of velocity (how fast). Velocity includes direction. A car in a circle at constant speed has changing velocity because the direction changes.
What is terminal velocity?
Terminal velocity is the constant speed when drag equals gravity. For a skydiver, about 55 m/s (200 km/h) spread-eagle, or 90 m/s (320 km/h) head-down.
How to convert m/s to km/h?
Multiply m/s by 3.6. Divide km/h by 3.6. For mph, multiply m/s by 2.237.