Distance-time graphs (cont.)
A distance-time graph shows the distance of a body from a starting point (y-axis) against time taken (x-axis).
The slope of the line on a distance-time graph represents speed, the steeper the line, the greater the speed it represents.
The SI unit of speed is metres per second (m/s)
Velocity and acceleration
Velocity is speed in a given direction. If the body changes direction it changes velocity, even if its speed stays the same.
If the velocity of a body changes, we say that it accelerates.
A velocity-time graph shows the velocity of a body (y-axis) against time taken (x-axis).
- The slope of the line represents acceleration
- If the slope is negative, the body is decelerating
- The area under the line on a velocity-time graph represents the distance traveled in the given time