Motion Graphs

Basic Definitions:

MOTION- the change in position measured by distance and time

SPEED - tells the rate at which an object moves

VELOCITY- tells the speed and direction of a moving object

ACCELERATION-tells the rate at which speed or direction changes

Position Time Graphs:

1. Horizontal Line (Zero Velocity)

- The object remains at rest.

-The position does not change over time.

Example: A parked car.

2. Straight Diagonal Line (Constant Velocity)

-A positive slope means the object moves forward at a constant speed.

- A negative slope means the object moves backward at a constant speed.

Example: A car moving at a steady speed.

3. Curved Line (Changing Velocity / Acceleration)

- A curve that gets steeper over time indicates increasing speed (acceleration).

- A curve that becomes flatter over time indicates decreasing speed (deceleration).

Example: A ball rolling down a hill.

4. Parabolic Curve (Uniform Acceleration)

- If the graph is a parabola opening upwards, the object is accelerating.

-If the parabola opens downward, the object is decelerating.

Example: Free-fall motion of an object

Velocity- Time Graphs:

1. Horizontal Line (Constant Velocity, Zero Acceleration)

-The object moves at a constant speed:

• If the line is above the time axis, the motion is forward.

• If the line is below the time axis, the motion is backward.

Example: A car on cruise control.

2. Straight Diagonal Line (Constant Acceleration or Deceleration)

• A positive slope means the object is accelerating:

• A negative slope means the object is decelerating.

Example: A car speeding up or slowing down at a steady rate.

3. Curved Line (Changing Acceleration)

• If the curve gets steeper, acceleration is increasing.

• If the curve flattens, acceleration is decreasing.

Example: A rocket launch.

4. Line Touching the Time Axis (Object at Rest)

• If the velocity is zero for a period, the object is stationary.

Example: A car stopped at a red light.