Graphing Sited and Acceleration Notes

Position vs Time Graphs

  • Positive Slope: Indicates forward movement.

    • Steeper slope = higher speed.

  • Horizontal Line: Indicates no movement.

    • Example: A boy resting on a bench or a car stopped at a light.

  • Negative Slope: Indicates movement back toward starting point.

    • Steeper slope indicates faster movement.

Curved Lines and Acceleration

  • Curved Line: Indicates changing speed, which is acceleration.

Real-life Example of Motion

  • Airplane Descent:

    • Segment A to B: Description of flight path.

    • Segment B to C: Changes in altitude and speed.

    • Segment C to D: Final approach.

Example of Jen's Journey to School

  • Analyze the graph representing distance traveled:

    • Each segment indicates distance changes relative to time.

Race Analysis Example

  • Distance vs Time Graph:

  • Participants: Albert, Bob, Charlie.

    • Identify who won, who rested, and calculate Albert's average speed.

Velocity vs Time Graph Analysis

  • Examine points A, B, and C on a velocity vs time graph to describe movement behavior.

Definitions and Key Vocabulary

  • Velocity: Speed with direction; includes displacement.

  • Vector: A quantity possessing both magnitude and direction.

  • Scalar: A quantity with only size; e.g., speed.

  • Acceleration: Change in speed/direction over time.

  • Constant Velocity: No change in speed; acceleration = 0.

  • Net Force: Sum of all forces on an object.

  • Balanced Forces: Equal forces acting on an object; results in no movement or constant speed.

  • Unbalanced Forces: Causes movement or changes in motion.

Understanding Changes in Acceleration and Velocity

  • Changes in velocity imply acceleration, including turning and cornering.

  • Formula to calculate acceleration:


    • [ \text{Acceleration} = \frac{\text{Final Velocity} - \text{Initial Velocity}}{\text{Time}} ]

Calculating Acceleration Examples

  • Practice problem: Cheetah accelerating from 0 m/s to 27 m/s in 3 seconds.

  • Another example with a hockey puck and Gabby Thomas.

Newton's Laws of Motion

  1. First Law: An object at rest stays at rest unless acted upon by an unbalanced force.

  2. Second Law: Acceleration is directly proportional to the net force and inversely proportional to mass.

  3. Third Law: For every action, there is an equal and opposite reaction.

Real-Life Examples of Newton's Laws

  • First Law: A soccer ball will not move until kicked; requires an external force.

  • Second Law: Greater force results in greater acceleration.

  • Third Law: Interaction between player and ball during a kick; different effects on acceleration due to mass differences.

Calculating Mass, Force, and Acceleration

  • Formula relationships:

    • [ F = m \times a ]

    • Rearranging for mass: [ m = \frac{F}{a} ]

    • Rearranging for acceleration: [ a = \frac{F}{m} ]

Practice Problems for Net Force

  • Applying balanced and unbalanced forces.

  • Calculate net force considering friction and other forces.

Summary of Key Concepts in Force

  • Net Force determines motion direction and acceleration.

    • When net force is zero = no acceleration.

    • If net force increases or decreases, so does acceleration.

Practical Applications of Newton's Laws

  • Analyze different scenarios to see how Newton's Laws manifest in everyday actions and motions, especially in sports and physical activities.